Math¶
Math task is used to perform arithmetic operations on the data. This task supports standard BODMAS expression with support for some inbuilt functions.
Table of Contents
Quick Start¶
Let us start with the following data which is a score card of a group of students for three subjects:
Student |
Science |
French |
English |
|---|---|---|---|
Alice |
78 |
65 |
81 |
Bob |
45 |
80 |
68 |
Jerry |
91 |
80 |
90 |
Rachel |
35 |
32 |
85 |
Complete the following steps to calculate the total number of Marks that the the students have received:
Open Data Preparation menu and click on Numeric Functions
Select Perform Math Function
In the expression box, build the expression:
Science + French + EnglishEnter “Total” into the new column box
Click APPLY
The result will appear as shown below:
Student |
Science |
French |
English |
Total |
|---|---|---|---|---|
Alice |
78 |
65 |
81 |
224 |
Bob |
45 |
80 |
68 |
193 |
Jerry |
91 |
80 |
90 |
261 |
Rachel |
35 |
32 |
85 |
152 |
Supported Options¶
Math task takes the following inputs:
expression: You can set a arithmetic expression.
Condition: See Condition
Apply result into: Using this you can apply the result into a new column of name. See result documentation
Arithmetic Expression¶
Arithmetic expression accepted by the math tasks supports the following arithmetic operators. +, -, *, /. These operands work on the following types of operands.
Numbers
Columns
Functions such as count, sum, avg. See Functions
Nested expression
Examples:
Let us assume that your original data is as shown below:
Student |
Science |
French |
English |
|---|---|---|---|
Alice |
78 |
65 |
81 |
Bob |
45 |
80 |
68 |
Jerry |
91 |
80 |
90 |
Rachel |
35 |
32 |
85 |
The valid expressions are:
2
3+4
“Science” + “French”
(“Science” + “French” + `”English”)/300
AVG(“Science”) - “Science”
INT((“Science” + “French” + `”English”)/3)
Note that the column names are put within a quoted string. The application shows hints to guide you to the right expression. If the expression is invalid, a warning is displayed at the bottom right of the expression box.
The expressions can be copied and pasted. You can paste an expression into a normal text editor like notepad, edit it and paste if back. The expression will work if it is valid.
The criterion for valid expression are:
Referring to the correct column names.
The braces are correctly opened, and
The functions used (such as SUM, COUNT) and so on, should have the correct parameters. See documentation for the functions and their parameters.
Expressions can be nested inside one another using parentheses. The following expressions are valid.
(10 + 20)/(20 + 40)
(10 - (20 + 40 * (100 -55)) + 20)
(10 * (20 + 40) + 20)/(“Science” + 10)
You can nest to as many levels. However, it is simpler to add more than one math rule at time to keep it simple and readable.
The results of the arithmetic expression is saved into a new column.
Handling empty values¶
When performing + - * / operations empty values
are treated as if they are zeroes.