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# cdfchi_x

Calculates the upper limit of integration of a cumulative chi-square distribution function.

## Prototype

```	function cdfchi_x (
p   : numeric,
df  : numeric
)

return_val  :  numeric
```

## Arguments

p

A multi-dimensional array or scalar value equal to the integral from 0 to return_val [0 < p < 1]

df

A multi-dimensional array or scalar value equal to the number of degrees of freedom of the chi-square distribution (0, +infinity).

## Return value

A array of the same size as x. Double if any of the input arguments are double, float otherwise.

## Description

Calculates the upper limit of integration of a cumulative chi-square distribution function.

The source code is from source routine "CDFCHI" from DCDFLIB (Double precision Cumulative Distribution Function LIBrary)

## Examples

```begin
p  = 0.95
df = 5.
x  = cdfchi_x (p,df)
print ("p="+p+"   df="+df+"   x="+x)
;  (0)     p=0.95   df=5    x=11.0705

end
```