1. The Frequency function
2. The histogram

CodePudding user response:

1. Give each group data, after the name of the selected, right-click, define the name, select the named region
2. The average:=SUMPRODUCT (x, f)/SUM (f)
3. The standard deviation:=SQRT (SUMPRODUCT (average (x -) ^ 2, f)/
4. Return to the corresponding array or the product of the area and the function of the
SUMPRODUCT (array1, array2)

CodePudding user response:

The following is about the content of the Matlab

CodePudding user response:

A weighted average and standard deviation
% odata=https://bbs.csdn.net/topics/load (' 1.3.2. TXT); % the load function is a function of open a text file containing the data only
X=data (:, 1);
F=data (:, 2);
A weighted average %
Xbar=x '* f/sum (f) % x, f are column vector, so x need to transpose
% weighted standard deviation
Sd=SQRT ((x - xbar). ^ 2 '* f/sum (f)) %. ^ 2 is refers to the corresponding element in the matrix multiplication