Computer Use Test 1

Fill handle

+ sign cursor when hovered on bottom right corner of selected cell in excel Used to drag things

Integrated circuit

- Allowed placement of many transistors onto a small surface (in small plastic or ceramic package so they are much closer together) - Silicon connections on silicon - Lowered cost, decreased space and made complex circuits simpler compared to using individual transistors (but lots of tech required to make these) - This enabled computers and other electronic devices to become smaller and cheaper to build and maintain - Today exceeding 10 billion transistors in a single package of approximately 25 square cm

2 main ways to represent information

- Analog data - Digital data

Internet

- At first the internet was not a thing and people were happy to use computers without a network - The US government project created a network that could withstand a nuclear war - Connection between computers that are self healing (had 2 connections to places as a back up mechanism- if one broke the other was sufficient) - Original purpose was transmitting data from 1 computer to another but eventually became really big

How spreadsheets/computers can help

- Calculations are fast - Visualizations are easy to add to aid understanding - Easy to model situations ("what if interest rates go up 0.25%)

Microsoft Excel document elements

- Cell - Row - Column - Worksheet - Workbook

Abacus

- First developed in Babylonia over 5000 years ago - Still used today in some parts of the world - A finger-powered pocket calculator

Margaret Hamilton

- Led the team who coded programming for the guidance computer - Considered a pioneer in software engineering - Figured out how to split a task among many people in order to complete something a single person could never do on their own (integrating the work of many into a single product)

Sphygmomanometer

- Mercury (extremely accurate, uses toxic metal, continuous) - Aneroid (less accurate, non-toxic, continuous) - Digital (pretty accurate, adequate precision for purposes, very easy to use, less interpretation necessary)

Spreadsheet applications

- Microsoft excel - LibreOffice Calc - Google sheets - Smartsheet - Quip - Zoho Sheet - Ether Calc - Airtable - ETC

Today's price/performance

- Over 3 billion operations per second costs less than $300 - Memory is measured in gigabytes not megabytes or kilobytes - Secondary storage is terabytes, soon to be petabytes - Communication speeds measure in megabits or gigabits per second not kilobits

Limitations to spreadsheets

- Speed of processing is not the highest possible (will CERN use them?, more serious math can use applications like MatLab) - Errors are often hard to notice * Detecting them requires some skill * Don't trust someone just because they show you a nice graph * Errors can have dramatic impacts

Origins of digital computers

- The earliest computing device was designed to aid numeric computation - Abacus

Desktop and portable computers- 1975 and later

- Use microprocessors - All-in-one designs, performance/price tradeoffs - Aimed at mass audience - Personal computers - Workstations

Xerox

- Well known for perfecting photo copying - Rich-lots of research labs (ex PARC)

Methods of entering data into cells in excel

-Type - Paste copied data - Program cells to generate data

Jacquard Loom

1801 An example of early programming in other fields (no calculations but programming) Used punch cards to define complex patterns woven into textiles Each dot signifies when you must switch the order of the threads (which is facing forward) Punch cards were later used to code computer programs

George Boole

1815-1864 Boolean algebra Laid logical foundations of digital computing circuitry Organizing possibilities (things you can say in english) in a logical way Formal way to describe logical decisions (explain how you derive a theorem) No calculations How it works: - A, B, and C represent various options - Answers (as you go down the columns) must only be true or false (represented by 0 or 1) Ex should you turn on or not turn on the heat

Grace Murray Hopper

1906-1992 Admiral in US navy, a programmer Wrote a tool that simplified her task- automating tasks: - Created first Compiler because she was tired of writing machine code by hand- greatly improved programming speed and efficiency Found the first computer bug

Alan Turing

1912-1954 Known for a couple of things: - Led the WWII research group that broke the code for the Enigma machine - Proposed the Turing Machine - Devised the Turing Test for Artificial Intelligence (way to test whether something is a computer or a person on the other side, Ex select all the images that contain a car is a version of a Turing Test)

Claude Shannon

1916 to 2001 Some of his contributions 1937: Introduced the application of Boolean Logic in creating digital computing machines 1948: Published "A mathematical theory of communication" which establishes the principles for encoding information so it might be reliably transmitted electronically - Derived formulas to predict and plan ahead of how many cables you need to run to transmit an electrical signal (based on size of wires)- Shannons limit (cannot break- reach a limit to how much signals can be transmitted based on how much wire you have) He bridged mathematic with electronic component Many consider him the father of the modern information age

Birth of the electronic computer time period

1930 to 1951 Contributors: - Claude Shannon - Von Neumann - Alan Turing

Colossus- Alan Turing

1943- Constructed an electronic computing machine to help decrypt German coded messages Created for a very specific purpose (not for general use) Ran through all possibilities that could have been used during encryption to determine if any produced human language Programmable so you can determine which letter on the keyboard would correspond to which output Basically sped up the decoding process

Age of the mainframes

1951 to 1970 Grace Murray Hopper IBM Margaret Hamilton Gordon Bell

Intel 4004 microprocessor

1972 - Invention of the microprocessor was a huge advancement - First commercially available microprocessor was first used in a programmable calculator - Made the personal computer possible - Contained 2300 transistors and ran at 100kHz

Radio Shack TRS-80

1978 - First plug and play personal computer available at retail (mostly for people who wanted to play video games- without going to the arcade) - Programmed in BASIC - Very successful - Very affordable - Limited commercial software - Created a cottage industry - Used cassette tapes for applications- took about 10 minutes to load

Osborne I

1981 - First "portable" personal computer - Came with lots of bundled software - Only weighed around 20 kilos (45 pounds) and sold for $1795 - At this time laptops were about twice as expensive as desk top computers (compared to the desk tops being more expensive today) - 5 inch (13cm) screen

Xerox Star

1981 Computer sold by Xerox for a while- not very popular

IBM PC

1982 - IBM's first personal computer - Significant shift for IBM - Open architecture (everyone was allowed to build computers under this standard technology- could build exactly the same kind of computer with the same devices built in with the same standards for peripherals)- this is where windows was born (used on many different kinds of computers now a days) * Why create this open architecture- wanted to sell a lot of computers but also wanted their's to be the standard/common model (to sell more computers and more software) - Established a new standard- legitimized the personal computer - Operating System supplied by Microsoft

Apple MacIntosh

1984 - Second personal computer with GUI interface - Adapted from the work done at Xerox - Designed to be a computer appliance for "real people" - Introduced at the 1984 Superbowl - Had a couple demo applications- advertising very important - Always targeting people better off than average (prices on the high side)

Algorithm

A finite set of unambiguous instructions to solve a problem From the name of the 9th century mathematician Muhammad ibn Musa al-Khwarizmi (latinized algorithmi) Early ex: - The Euclidean algorithm for finding the greatest common divisor of 2 numbers (300 BC) - The sieve of Eratosthenes for finding prime numbers (60-120 AD)

Who worked on ENIAC

A lot of the people who worked on it (early programmers) were women- selected ones who were already doing telephone switch boards (good memory) and that were smaller in size Maintenance was a mans job

Lookup_range

A single row or column with data sorted in ascending order that the lookup function searches

Advanced Research Projects Agency Network

ARPANET -Large-area computer network, established in 1969 - Allowed universities to share data (those in california, stanford, those in utah) - Communication protocols developed for ARPANET in early 1980's served as the basis for the Internet

Age of the personal computers

After 1970

Workbook

Another name for an Excel document A workbook contains at least one worksheet

Going to the moon

Apollo space program depended on computers to calculate trajectories and control guidance - Trajectories calculated using IBM mainframes - On board guidance computer had less processing power than modern appliances, but had auto-pilot capabilities - Margaret Hamilton was a key player in this

Steve Wozniak

Apple cofounder

Calculating and classifying BMIs of 500 adults

BMI= weight (kg)/ (height (m))^2 Step1: Calculate BMIs for the sample of adults - Name variables (named references in formulas are neater than using direct references) - Write the formula in a cell and fill down (be careful of units - Can calculate averages using: average() Step2: Use the lookup function to search the BMI_Classification table - use: lookup(value, lookup_range, [result_range])

How to add more than 1 row/column at a time

Before clicking insert highlight the number you want to create

Creating a numeric series

Can go up by any non-zero term (not just 1) Steps: Enter first few numbers of series Highlight them Use fill handle OR Hold Ctrl when dragging OR Use menu

CPU

Central processing unit The electronic circuitry within a computer that executes instructions that make up a computer program It handles basic instructions and allocates the more complicated tasks to other specific chips to get them to do what they do best.

Discrete vs continuous and computers

Computers are finite (discrete) and deterministic (not random) - They can only operate on a fixed amount of data at a time - The amount and type of data must be known ahead of time Yet information is often represented in an infinite range How to do this? - Represent enough of the range to meet our computational needs (must throw away some info but make a choice as to how much can be thrown away without losing anything of value- make informed decision)

Conversion of analog to digital data in 2 steps

Computers cannot work well with analog information so here are the steps to convert to digital: 1. Sampling (discretization) AKA quantization - Converts continuous variation to discrete snapshots/samples (at regular intervals) - Ex digitization of video- 24-30 still frames per second 2. Quantization (truncation) - Converts infinite range of values to a finite one, approximate the quantities - Ex 1/3=0.33333 (some finite number of digits) - Ex pi=3.14159 - With irrational numbers (such as pi) you must lose info (can not do anything about it unless you present in a way with infinite precision, ex pi)

Innovations of computers after the 1950s

Computers got smaller over time since the 1950's This is done by optimizing circuits and making the tubes smaller

Analog data

Continuous representation Analogous to the actual information it represents Picture- smooth line (can have as many intermediate values as you wish- within the size of carbon atoms that form the trace) Ex spirit (or mercury) thermometer provides infinite precision (our reading is limited only by our ability to measure its value), accuracy is dependent on manufacturing quality

Electrical vs Electronic

DIFFERENT Electrical- wires that directly connect pieces together (always a direct connection between component 1 and 2), there is a mechanical aspect (the machine is not able to configure itself without a mechanical movement), not related to flow of electrons Electronic- can change direction of flow of electricity (can be done without any mechanical means), relies on tubes (that control the flow of electrical signals)

Functions in excel

Data in cells can be processed by using one or more built-in math or logical operations or functions Must be preceded by the = sign Should include constants and/or valid cell references or names No circular references In the form: func(var1,var2...)

Gordon Bell

Developed first minicomputers in 1960-1983 Digital Equipment Corporation (DEC) Brough computing to small business (old larger computer were too expensive, only big companies could afford) Created major competition for IBM, Univac, who only bulit mainframes Made Boston area first silicon valley "Mini"- smaller, fits in the corner of 1 room

Digital data

Discrete representation Using a finite number of digits (or any other set of symbols) to record the data Picture- can only represent integer values, therefore a bunch of data points not smooth (can only have data points of a specific accuracy Ex digital displays (digital clock, results in information being lost in the digitization)

1st electronic general-purpose computer

ENIAC

ENIAC

Electronic Numerical Integrator And Computer 1st general-purpose electronic digital computer - Could do almost everything modern day computers can - Commissioned by the US army for computing ballistic firing tables - Used vacuum tubes (about the size of a thumb) to control the flow of electrical signals- unreliable (could crack, burn out or overheat) - Massive scale (size) - Redundant design - Decimal internal coding - Operational in 1946 - Must move wires from 1 location to another (to connect 2 different things) - Manual programming of boards, switches, and function table

Why are spreadsheets important

Few people can do mental math effectively Few people can fully understand the math concepts

Specialized supercomputers

First developed in the late 1970's High-performance systems used for scientific applications (weather forecasting, code breaking) Advance special purpose designs IBM, NRCPC, NUDT, Dell EMC, Cray, NEC, etc Circular to minimize length of connections between components Built specifically to do very advanced simulations

Altair 8080

First kit micro computer 1975 First affordable computer Using microprocessors from Intel

Circular references

Function or operations should not contain references to the cell containing them

Naming cells/ranges of cells

Highlight cell(s) Write the name in the Name Box OR Select Define Name option within the Formulas tab group

Supercomputers today

IBM Summit supercomputer is an example of one Used for hydrodynamics, quantum chemistry, molecular dynamics, climate modeling, and financial modeling

Transistors and computer advancements

If transistors are closer- more in synch If transistors are smaller- much more energy efficient and faster (less overheating) By making transistors smaller and closer together you make the computers smaller and faster- this is how they were advanced (faster and more power efficient) for a long time This is not really how we are making them faster now

The beginning of Microsoft

In 1975 Bill Gates and Paul Allen approached Ed Roberts of MITS (the company that developed the Altair) and promised to deliver a BASIC compiler They did so and from that sale, Microsoft was born AKA Bill Gates and Paul Allen were asked to convert programming language to more everyday language

I/O

Input Output The communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system.

IBM System/360

Introduced in 1964 Family of computers with compatible architecture, covering a wide price range Established the standard for mainframes for a decade and beyond- therefore establishing the common playing grounds so other companies could develop software IBM is one of the oldest companies to start making computers Why called main frame?- the way it was built, metal frame (now used to describe any computer doing anything very complicated that is shared by many operators)

The Enigma machine

Invented in 1918 It was the most sophisticated code system of its day, a priority for the Allies to break it as the Germans believes it was unbreakable

Myth- apple was created in a garage

It was created in a very fancy rich kid garage Had to be well off to afford the equipment in the garage Steve Wozniak said they did no designs there, there were hardly ever more than 2 people in the garage and mostly they were sitting around kind of doing nothing

Vacuum tubes

Large Generate a lot of heat Prone to fail Replacing a bad (broken) one meant checking among ENIAC's 19000 possibilities

Early calculating machines

Manual or mechanical Ex: - Slide rule- was used in science and engineering in 1600's until it was replaced in 1900's (1970's) by pocket calculators, you slide to reveal the results of a calculation, can get up to 3 digits of precision, easy to use - Mechanical calculators (since 1600's)- mechanical machine, no programming required

Bill Gates

Microsoft cofounder

Why the garage myth

No one wants to hear the story of the rich, well-connected guys who meet up at a Marriott conference room to hatch a business plan

Moore's Law in action

Not really a law more of an observation: Every few years the density of transistors was increasing by the same amount (decreasing in size by the same amount every year- about half the size) However we will eventually see a flat horizontal line in this graph because this is not how we are making computers faster anymore

DEC PDP series

Offered mainframe performance at a fraction of the cost PDP-8 introduced at 20 000 vs 1 mil for a mainframe (early 1960 dollars.

Result_range

Optional A row or column the same size as lookup_range If value lies within one of the ranges specified in lookup_range, the function returns the matching data stored in result_range AKA it is the output

Features of spreadsheet apps

Organize tabular data - Gridded layout for numeric and non-numeric data - Options to format data - Ability to import formatted data from other sources Manipulate, process, transform, generate, or analyze data - Basic operations (ex arithmetic, logical) - Functions, programmable cells Visualize data - Numbers or text - Charts and graphs

Xerox Palo Alto Research Center

PARC Contributions to computing include: - Ethernet networking technology - Laser printers/copiers - Object-Oriented Programming (OOP)- programming paradigm workstations Alto and Star were the first to use a window-based Graphical User Interface (GUI) - In other words everything controlled through mouse- major innovation - Ideas taken by both Bill Gates and Steve Jobs - Black and white because colour screens were too expensive

Problems with computers we are working towards solving today

Problem today is not the computing powers but the algorithms- trying to imitate human functions but faster Trying to predict things that are not textbook/predictable but rather real world (ex self-driving Tesla crashing due to very reflective car- only seeing reflections of world and so did not recognize vehicles) Operations per second-speed

Google would like you to believe it started in a garage as well- myth

Silicon Valley companies (especially big ones), love to talk about being founded in a garage, its a popular founding myth Google had already received a million dollars in venture capital before using the garage Trying to make it seem like anyone that has a garage could do this- not true: Required expensive equipment, good education, time (instead of being at a job to supper themselves doing this)

Turing Machine

Simple abstract universal machine model for defining computability Predicts whether something can or cannot be done/calculated by a computer How: - Simplified the CPU extensively but in a way that the simplified version can do all that the complex ones can do but would just take a lot longer - Easier to analyze this simple computer (in terms of determining whether something is computable by an algorithm) - Then apply this conclusion to the complex computer

Von Neumann Architecture

Some of his contributions: - "Stored program"- determined how you can record a program (similar to punch cards used for textiles), keeping the numbers and commands that direct those numbers (instructions) in the same location - Binary internal coding (decided to switch everything to binary) - CPU-Memory-I/O organization (Central processing unit, a memory, mass storage, IO) * varies in degree of complexity - "fetch-decode-execute" instruction cycle- in order to make the program respond the same way no matter the complexity of the CPU memory organization * most of the same commands exist today (even though the CPU organization is completely different) * Fetch- get CPU info * Decode- determines what to do * Execute- does it (responds the same way no matter the complexity) - Earlier computers (ex ENIAC) hard-wired to do one task, re-wired for different ones - Stored program computer can run different programs - Basis for modern computers

Myth- 640K ought to be enough for anybody

Statement about the amount of memory that should be good for everyone Bill Gates said that he's said some stupid things and some wrong things but not that one (that 640K ought to be enough for anybody) There is no evidence that he ever said that- so he denied it

Apple

Steve Wozniak and Steve Jobs 1st Apple computer came out in 1976

GUI

The graphical user interface (GUI /ˈɡuːaɪ/ gee-you-eye) is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicator such as primary notation, instead of text-based user interfaces, typed command labels or text navigation. AKA everything controlled through a mouse

Transistor

The most important invention of the 20th century Replaced vacuum tubes which were bulky and prone to breaking Even though at this time the electronic tubes were faster than the transistors (though eventually this changed) they required way more energy

2nd device to be built with transistors

The transistor radio

Original function of the trash icon

To eject floppy disk once icon was dragged in

Where are text formatting tools

Under Home tab

Ancient history of computers time period

Up to 1930 Contributors: - George Boole

Create a series of numbers from one number

Use fill handle Repeats entry over and over again

Punch cards

Used by student programmers using the IBM 026 keypuncher They were used to write applications- affordable way to program (cheaper than 360)

Compute bugs

Used to describe when a program is not working as it should The first one was an actual bug stuck in a computer- found by Grace Murray Hopper

Graphs

Various graph types can be generated in Excel depending on type of data and choice

Early computer programming

Was slow, tedious and repetitious

Tool tips

When you hover over icons for tips on what they do

Digital vs analogue

With a limited number of possible values digital (discrete) is more convenient to analyze- easier to analyze discrete values (less interpreting involved-easier) Note- digital/discrete scales can involve numeric values or words or letter or symbols

Chart tools tab

Within the Tools menu

Worksheet

Workspace containing multiple rows and columns where data is stored and manipulated Worksheets can be (re)named on the worksheet tab and referenced accordingly Can have multiple in a workbook

Does 0.99999999 (infinite number of 9's) = 1.00000000000 (infinite number of 0's)

Yes Can not find a number that fits in between them

Is it OK if information is lost

Yes some information can be lost BUT: - We decide what can be lost at the very beginning - There are many mechanisms to determine proper parameters to digitize analogue data with as much precision as necessary * Nyquist-Shannon sampling theorem * Quantization error models - Any losses are completely avoidable after the digitization is performed

How to graph functions in excel

You can graph functions by generating a series for the x values Then in a y column insert the equation (with a direct reference to the corresponding x cell where the variable x is in the equation) You should be able to only fill in the first y column cell and drag down to fill the rest Steps to insert graph: - Click a location where you want to display the graph - Select Insert Line Chart within the Insert tab and choose the first 2D line in the dropdown - Click Select Data within the Chart Tools Design tab to start the process of selecting the data to be plotted (Select Data (Source) window appears) - Click Add in the Legend Entries box (an Edit Series window appears) - Delete any entry in the Series Values box - Within the Series Values box delete any entry currently there. Click the first numerical value of y and drag downwards to select all values of y to be plotted. Click OK to save the selection - Click Edit in the Horizontal Axis Labels window (an Axis Labels window appears) - With the Axis label range box selected, click the first numerical value of x and drag downwards to select all values to be plotted. Click OK to save the selection - The Select Data Source window reappears. Click OK to apply all entries and plot the graph

First device built with transistors

Zenith Royal-T "tubeless" hearing aid Built in 1953