# [R] Integrate(dnorm) with different mean and standard deviation help

Peter Ehlers ehlers at ucalgary.ca
Tue Jul 24 04:54:45 CEST 2012

```On 2012-07-23 19:48, Pascal Oettli wrote:
> Hello,
>
> Maybe the following could help:
>
>   > f <- function(x) dnorm(x, mean=2, sd=1)
>   > integrate(f, -1.96, 1.96)
> 0.4840091 with absolute error < 1.4e-12

Or you could note the '...' argument indicated on the help page:

integrate(dnorm, lower = -1.96, upper = 1.96,
mean = 2, sd = 1)

Peter Ehlers

>
> HTH
>
> Regards.
>
>
> Le 24/07/2012 11:23, FJ M a écrit :
>>
>> I'm trying to provide different parameters to the integrate function for various probability functions. I'm using dnorm as the simplest example here. For instance integrate(dnorm, -1.96, 1.96) produces the correct answer for a normal distribution with mean 0 and standard deviation 1. I've tried two ways to use mean=2.0 and standard deviation 1, but with no luck. The examples follow.
>>
>>
>>> integrate(dnorm, -1.96, 1.96)
>> 0.9500042 with absolute error < 1e-11
>>> mean = 2.0
>>> sd = 1.0
>>> integrate(dnorm, -1.96, 1.96)
>> 0.9500042 with absolute error < 1e-11
>>> integrate(dnorm(mean=2.0,sd=1.0), -1.96, 1.96)
>> Error in .Internal(dnorm(x, mean, sd, log)) : 'x' is missing
>> Calls: integrate -> match.fun -> dnorm
>> Execution halted
>>
>> How do I change the built in mean=0 and standard deviation=1 for dnorm using integrate?
>>
>> Thanks,
>>
>> Frank
>> Chicago, IL
>> 	[[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> and provide commented, minimal, self-contained, reproducible code.
>

```