Mathematica/Elementary
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These are draft notes from An Elementary Introduction to the Wolfram Language
- Starting Out: Elementary Arithmetic (4:10)
- Shift-Enter to perform a calculation
- ^ for powers
- asterisk for multiplication or space if it is clear
- Keeps numbers as rational fractions if possible; converts to float with any floats involved
- Introducing Functions (6:09)
- Commands use CamelCase
- Arguments in square brackets
- Colors: Blue=unknown command, purple=bracket mismatch
- Plus, Times, Power, Max, Min, RandomInteger
- First Look at Lists (6:26)
- Usually with { }
- Edit->Extend Selection or CTRL-. will "grow" a selection to the next largest complete expression
- ListLinePlot, ListPlot, Reverse, Range, Join
- Range starts with 1
- Displaying Lists (4:54)
- CTRL-= for natural language input
- Graphics can be part of a list
- BarChart, PieChart, NumberLinePlot, Colulmn,
- Operations on Lists (6:17)
- List math operations are element-wise
- [[ ]] will index from list
- Sort, Length, Total, First, Last, Part, Take, Drop, Count, IntegerDigits
- Mathematica is 1-indexed
- Making Tables (9:34)
- Table
- Table[item, number of items to generate]
- Table[fcn[var], {var, start, end}]
- Table[fcn[var], {var, start, end, step}]
- Table[fcn[var], {var, {values}}]
- The video has "ListPlot[Range[0, 1, 0.02]-Range[0, 1, 0.02]^2]" but "ListPlot[Table[x - x^2, {x, Range[0, 1, 0.02]}]]" seems more efficient
- Table
- Colors and Styles (7:22)
- Red, Green, Blue, ColorNegate, Blend, RGBColor, Hue, RandomColor
- Style takes an item along with information about color, size, and face
- Basic Graphics Options (7:54)
- Graphics expression has graphics primitives that are changed by graphics directives
- Graphics, Circle, Disk, RegularPolygon, Graphics3D, Sphere, Cone
- Wrap graphics primitives with Style to change things
- Thickness, Opacity
- Interactive Manipulation (7:30)
- Manipulate creates a selector; effectively picks items from a list but can continuously change if variable is continuous
- Can manipulate multiple items
- polyfit example?
- ColorSetter
- Images (5:22)
- Importing the sample file did not work for me, nor did CurrentImage[] so I just imported another jpg I had
- Import, Blur, Binarize, EdgeDetect, DominantColors, ImageAdd, ImageCollage, ExampleData
- Strings and Text (7:55)
- Double quotes
- InputForm, StringLength, StringReverse, ToUpperCase, StringTake, StringJoin, Characters, TextWords, TextSentences, WikipediaData, WordCloud, WordList, RomanNumeral, IntegerName, AlphaBet, LetterNumber, FromLetterNumber, Transliterate, Rasterize
- StringLength and others are mapped onto lists of strings
- Sound (8:32)
- Sound, SoundNote
- Note 0 is middle C, integer values are keys (including black keys) away from middle C
- To choose a style you also have to choose a duration
- Sound, SoundNote
- Arrays, or Lists of Lists (6:59)
- Table with extra sizes
- Grid, ArrayPlot, ImageData
- ArrayPlot colorizes in reverse...ArrayPlot[ImageData[image]] is reversed
- Coordinates and Graphics (7:57)