Using Defer to leave expressions unevaluated for a quick quiz. Code is spelled out so the process is obvious:

someFractions := Table[r, {r, 1/10, 9/10, 1/20}]
Print@Column@
  MapThread[
   Row[{Defer[#1 + #2], " = "}] &, {RandomSample[someFractions], 
    RandomSample[someFractions]}]

BUT regular Thread with Grid is aligned more neatly:

Grid@Thread[{RandomSample[someFractions], " + ", 
   RandomSample[someFractions], " = "}]

NUMBERED:

Grid@Thread[{ToString[#] ~~ "." & /@ Range[Length[someFractions]], 
   RandomSample[someFractions], " + ", RandomSample[someFractions], 
   " = "}]

ExampleData is a file archive in the Mathematica installation layout

FindFile["ExampleData/elements.xls"]

(* "C:\Program Files\Wolfram Research\Mathematica\12.1\Documentation\English\System\ ExampleData\elements.xls" *)

ExampleData is also a curated data function with the same name but serving a slightly different purpose

http://reference.wolfram.com/language/ref/ExampleData.html

For May 18 & 19 Challenge:

A slightly different approach. You can select the number of sides n via a slider. The default color is Orange, RGBColor[1,0.65,0]. A different color can be chosen via the color slider.

c = RGBColor[1, 0.65, 0];
c -> Dynamic[c];
Manipulate[Graphics[Style[RegularPolygon[n], c]], {n, 3, 20, 1}, 
 Column[{ColorSlider[Dynamic[c]]}], LocalizeVariables -> False]

After playing with numbers and colors, the number of sides and the RGBColor can be extracted.

n // InputForm
ColorConvert[{c}, "RGB"] // InputForm

Amino = <|"D" -> RGBColor["#E60A0A"], "E" -> RGBColor["#E60A0A"], 
   "C" -> RGBColor["#E6E600"], "M" -> RGBColor["#E6E600"], 
   "K" -> RGBColor["#145AFF"], "R" -> RGBColor["#145AFF"], 
   "S" -> RGBColor["#FA9600"], "T" -> RGBColor["#FA9600"], 
   "F" -> RGBColor["#3232AA"], "Y" -> RGBColor["#3232AA"], 
   "N" -> RGBColor["#00DCDC"], "Q" -> RGBColor["#00DCDC"], 
   "G" -> RGBColor["#EBEBEB"], "I" -> RGBColor["#0F820F"], 
   "L" -> RGBColor["#0F820F"], "V" -> RGBColor["#0F820F"], 
   "A" -> RGBColor["#C8C8C8"], "W" -> RGBColor["#B45AB4"], 
   "H" -> RGBColor["#8282D2"], "P" -> RGBColor["#DC9682"]|>;

ClearAll[colorResidues];
Options[colorResidues] = {ColorScheme -> Amino};

colorResidues[sequence_, opts : OptionsPattern[{colorResidues, Framed}]] :=
  sequence // Characters //
    Map[Framed[#,
       Background -> OptionValue[ColorScheme][#],
       FilterRules[{opts}, Options[Framed]]] &] //
    Row

muc6 = StringTake[ProteinData["MUC6", "Sequence"], 75];

colorResidues[muc6]

Options for Framed can be provided

colorResidues[muc6, FrameStyle -> None]

colorResidues[muc6, FrameStyle -> None, RoundingRadius -> 4]

colorResidues[muc6, FrameStyle -> {Thin, Blue, Dotted},
  RoundingRadius -> 4, ImageMargins -> 2]

Use a random ColorScheme

colorResidues[muc6, FrameStyle -> None, 
 ColorScheme -> (Amino /. _RGBColor :> RandomColor[] // Map[Evaluate])]

That's clear and concise code :)

I didn't realise there is RegularPolygon function in Wolfram language, so here's a bit longer way to do the same with trigonometric approach:

poly[n_Integer/;n>2]:=Graphics[{Orange,Polygon[Table[{Cos[2 Pi k/n],Sin[2Pi k/n]},{k,1,n}]]}]

and with the extra color argument:

poly[n_Integer/;n>2, c_RGBColor:RGBColor[1, 0.5, 0] ]:=Graphics[{c,Polygon[Table[{Cos[2 Pi k/n],Sin[2Pi k/n]},{k,1,n}]]}]

Hi folks - I just did Quiz 3 there and noticed that there were issues in selecting certain answers. Particularly in being able to choose answer a. for Problem 3. I could select b, c or d without any problems but when trying to select a. the cursor changes to the font edit cursor and thus does not allow clicking of the button.

I tried in Chrome and in Firefox and both had the same issue

To get around this, I clicked "Make Your Own Copy" of the Quiz and then in that was able to edit the problem questions in that file. All I had to do was hit return between the question text and the answers, then answer a. was able to be selected again normally.

I saw someone mentioned this the other day during one of the lectures, so this is a workaround if anyone is experiencing this same issue. Also, I guess the Wolfram staff could edit the master so as to avoid this issue? I believe Problems 2, 3 and 9 have the same issue and in all three cases it's because the answers are too close to the question text.

Hello, all! Nothing fancy, just the straight dope with an error message if necessary.

poly[n_] /; If[TrueQ[n >= 3], True, Message[poly::badint, n]; False] := Graphics[{Darker@Orange, RegularPolygon[n]}]

poly::badint = 
  "OOPS! The integer `1` should be greater than 2. TRY AGAIN!";

Dear Wolfram Study Group,

I'm trying to solve the auto-graded tasks for the Wolfram Technology Certified Level 1 Certificate and I guess there are technical issues with some of them. Task 1.4 asks for random strings so my solution (being random) does not match the expected output. I am quite sure that my code is correct. Can I maybe send it to you somehow (in order to not reveal solutions I did not post it here in the forum)? The same problem occures with task 1.8 (the spheres are randomly positioned). Suprisingly, my solution, despite not matching the expected output, is marked as correct for task 1.7 which also involves randomness. For task 1.11 I get the expected output on my local machine using Mathematica 11 but the exact same code throws many errors like "GenomeData::notent : 381 is not a known entity, class, or tag for GenomeData. Use GenomeData[] for a list of entities." when executed in the online notebook. For task 1.13, my code executes in the cloud notebook, yielding the expected output (or at least output which is visually not distinguishable from it), but is still marked as incorrect. The same seems to happen for task 1.14 (altough I can not compare the images by hand), 1.15., 1.18 and 1.20. What should I do? Can I maybe send you my solutions in my own notebook?

Best regards

Yorick Zeschke

The June 5th deadline is for the four quizzes that you must complete for the Certificate of Program Completion.

We have not yet sent out the link to the exercises that need to be completed for the Level I certification. You will have at least two weeks to complete the exercises.

We've tried to fix this on our end. Let us know if you continue to see issues.

The function works after a fashion but am slightly confused about how spacing works in graphics row.To make matters worse, I seem to be able to select and drag the image to achieve whatever spacing I desire. Perhaps you can advise on what is lacking. colorResidue[proteinSeqNameString, seqStartPosInteger, seqEndPosInteger, spacingInteger, colSchemeList /; MatchQ[colScheme, {Rule[String, _?ColorQ] ..}]] := GraphicsRow[ Characters[ StringTake[ ProteinData[ToUpperCase[proteinSeqName], "Sequence"], {seqStartPos, seqEndPos}]] /. x_String :> Style[Framed[x, FrameStyle -> {Black, Thick}], ColorNegate[x /. colScheme], Background -> x /. colScheme] , Spacings -> spacing]

Here's something very basic we could start with (no options and no error-handling at all):

ColorResidues[seq_String] := 
 With[{aa = Characters[seq]}, 
  Row[Panel[#, Background -> Amino[#]] & /@ aa]]

Hi Abrita,

Amino does not have a color for "I" which appears in the sequence.

Last challenge for this week: From Paul Wellin's "Essentials of Programming in Mathematica"

Create a function ColorResidues[seq] that takes an amino acid sequence seq and returns a visualization like that below where the amino acids are colored according to a scheme such as Amino, where more polar residues are brighter and more nonpolar residues are colored darker. In addition to a color scheme option add options to control the frame around each residue.

Note: Changing Amino to an Association. I think that will work better. Also for reference, I got the colors from http://life.nthu.edu.tw/~fmhsu/rasframe/SHAPELY.HTM

Amino = <|"D" -> RGBColor["#E60A0A"],
  "E" -> RGBColor["#E60A0A"],
  "C" -> RGBColor["#E6E600"],
  "M" -> RGBColor["#E6E600"],
  "K" -> RGBColor["#145AFF"],
  "R" -> RGBColor["#145AFF"],
  "S" -> RGBColor["#FA9600"],
  "T" -> RGBColor["#FA9600"],
  "F" -> RGBColor["#3232AA"],
  "Y" -> RGBColor["#3232AA"],
  "N" -> RGBColor["#00DCDC"],
  "Q" ->  RGBColor["#00DCDC"],
  "G" -> RGBColor["#EBEBEB"],
  "I" -> RGBColor["#0F820F"], 
  "L" -> RGBColor["#0F820F"],
  "V" -> RGBColor["#0F820F"],
  "A" -> RGBColor["#C8C8C8"],
  "W" -> RGBColor["#B45AB4"],
  "H" -> RGBColor["#8282D2"],
   "P" -> RGBColor["#DC9682"]|>

muc6 = StringTake[ProteinData["MUC6", "Sequence"], 75]

Would you post links to documentation on overloading functions and remembering calculated values? The code I captured looks like

fib[0]:=1
fib[1]:=1
fib[x_]:=fib[x]=fib[x-1]+fib[x-2]