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Computes the maximum value found in all row values in a column. Inputs can be Integer, Decimal, or Datetime.
  • When used in a pivot transform, the function is computed for each instance of the value specified in the group parameter. See Pivot Transform.
  • If a row contains a missing or null value, it is not factored into the calculation.
  • If no numeric values are found in the source column, the function returns a null value.

For a version of this function computed over a rolling window of rows, see ROLLINGMAX Function.

Datetime inputs to this function return Unixtime values.

Wrangle vs. SQL: This function is part of Wrangle , a proprietary data transformation language. Wrangle is not SQL. For more information, see Wrangle Language.


Basic Usage

max(myRating)

Output: Returns the maximum value of the myRating column.

Syntax and Arguments

max(function_col_ref) [group:group_col_ref] [limit:limit_count]


ArgumentRequired?Data TypeDescription
function_col_refYstringName of column to which to apply the function

For more information on the group and limit parameters, see Pivot Transform.

For more information on syntax standards, see Language Documentation Syntax Notes.

function_col_ref

Name of the column the values of which you want to calculate the maximum. Inputs must be Integer, Decimal, or Datetime values.

NOTE: If the input is in Datetime type, the output is in unixtime format. You can wrap these outputs in the DATEFORMAT function to generate the results in the appropriate Datetime format. See DATEFORMAT Function.

  • Literal values are not supported as inputs.
  • Multiple columns and wildcards are not supported.

Usage Notes:

Required?Data TypeExample Value
YesString (column reference)myValues


Examples

Tip: For additional examples, see Common Tasks.

This example illustrates how you can apply statistical functions to your dataset. Calculations include average (mean), max, min, standard deviation, and variance.

Source:

Students took a test and recorded the following scores. You want to perform some statistical analysis on them:

StudentScore
Anna84
Ben71
Caleb76
Danielle87
Evan85
Faith92
Gabe85
Hannah99
Ian73
Jane68

Transformation:

You can use the following transformations to calculate the average (mean), minimum, and maximum scores:

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula AVERAGE(Score)
Parameter: New column name 'avgScore'

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula MIN(Score)
Parameter: New column name 'minScore'

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula MAX(Score)
Parameter: New column name 'maxScore'

To apply statistical functions to your data, you can use the VAR and STDEV functions, which can be used as the basis for other statistical calculations.

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula VAR(Score)
Parameter: New column name var_Score

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula STDEV(Score)
Parameter: New column name stdev_Score

For each score, you can now calculate the variation of each one from the average, using the following:

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula ((Score - avg_Score) / stdev_Score)
Parameter: New column name 'stDevs'

Now, you want to apply grades based on a formula:

Gradestandard deviations from avg (stDevs)
AstDevs > 1
BstDevs > 0.5
C-1 <= stDevs <= 0.5
DstDevs < -1
FstDevs < -2

You can build the following transformation using the IF function to calculate grades.

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula IF((stDevs > 1),'A',IF((stDevs < -2),'F',IF((stDevs < -1),'D',IF((stDevs > 0.5),'B','C'))))

For more information, see IF Function.

To clean up the content, you might want to apply some formatting to the score columns. The following reformats the stdev_Score and stDevs columns to display two decimal places:

Transformation Name Edit column with formula
Parameter: Columns stdev_Score
Parameter: Formula NUMFORMAT(stdev_Score, '##.00')

Transformation Name Edit column with formula
Parameter: Columns stDevs
Parameter: Formula NUMFORMAT(stDevs, '##.00')

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula MODE(Score)
Parameter: New column name 'modeScore'

Results:

StudentScoremodeScoreavgScoreminScoremaxScorevar_Scorestdev_ScorestDevsGrade
Anna8485826899

87.00000000000001

9.330.21C
Ben718582689987.000000000000019.33-1.18D
Caleb768582689987.000000000000019.33-0.64C
Danielle878582689987.000000000000019.330.54B
Evan858582689987.000000000000019.330.32C
Faith928582689987.000000000000019.331.07A
Gabe858582689987.000000000000019.330.32C
Hannah998582689987.000000000000019.331.82A
Ian738582689987.000000000000019.33-0.96C
Jane688582689987.000000000000019.33-1.50D

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