Data analysis labNumPy

50 NumPy problems

Solve them in order. Each problem is one notebook: write the answer, run it, then open the solution and compare. Mark a problem done when you can solve it without looking.

0 of 50 marked done

Create arrays

  1. 01Build an array from a listeasy
  2. 02A row of zeroseasy
  3. 03A square of oneseasy
  4. 04Even numbers with arangeeasy
  5. 05Five points from 0 to 1easy
  6. 06A 4 by 4 identityeasy
  7. 07Fill a block with one valueeasy
  8. 08Numbers 0 through 8 as a grideasy

Index and slice

  1. 09First and last itemeasy
  2. 10Every other itemeasy
  3. 11Reverse the arrayeasy
  4. 12One row of a tableeasy
  5. 13One column of a tablemedium
  6. 14The last two columnsmedium

Masks

  1. 15Keep the values above 10easy
  2. 16Turn negatives into zeromedium
  3. 17Count the even numberseasy
  4. 18Clip into a rangemedium
  5. 19Index of the largest valuemedium
  6. 20A closed intervalmedium

Broadcasting

  1. 21Add a bonus to every rowmedium
  2. 22Scale each columnmedium
  3. 23An outer summedium
  4. 24Center each rowmedium
  5. 25Divide each column by its maxmedium
  6. 26Distances between every pairhard

Reductions

  1. 27Sum and meaneasy
  2. 28Mean of each columneasy
  3. 29Sum of each roweasy
  4. 30Spread of a samplemedium
  5. 31A running totaleasy
  6. 32Mean that skips missing valuesmedium

Shape

  1. 33Reshape into a tableeasy
  2. 34Swap rows and columnseasy
  3. 35Flatten a tableeasy
  4. 36Stack two rowsmedium
  5. 37Place two columns side by sidemedium
  6. 38Split into equal partsmedium

Order

  1. 39Sort high to loweasy
  2. 40The order of the original scoresmedium
  3. 41How often each label appearsmedium
  4. 42Where a new score would sitmedium

Linear algebra

  1. 43Dot productmedium
  2. 44A matrix times a vectormedium
  3. 45Multiply two matricesmedium
  4. 46Length of a vectormedium
  5. 47Determinant of a 2 by 2hard
  6. 48Solve a two-equation systemhard

On the Iris data

  1. 49Mean of each Iris measurementmedium
  2. 50How many long petals?medium

The lessons behind these problems are in the NumPy course.