Why this package installed by npm is not found

Question

I am working on Debian Stable Linux which is updated and working very well.

I have installed a compute-pcorr package globally with following npm command:

$ sudo npm install compute-pcorr -g

It is listed with following npm command:

$  npm list -g --depth=0 
/usr/local/lib
├── compute-pcorr@1.0.0
└── ml-stat@1.3.3

I am now trying following code demo code from its homepage:

var pcorr = require( 'compute-pcorr@1.0.0' ); 

var x = [ 1, 2, 3, 4, 5 ]; 
var y = [ 5, 4, 3, 2, 1 ];

var mat = pcorr( x, y );
Console.log("Correlation Matrix: "+ mat)

However, when I run above code, I get error:

$ node compute_pcorr_usage.js 

internal/modules/cjs/loader.js:818
  throw err;
  ^

Error: Cannot find module 'compute-pcorr@1.0.0'

Following in code is also not working:

var pcorr = require( 'compute-pcorr' );

I also tried to reinstall package with following command, but error persists:

sudo npm install compute-pcorr -g --save

Where is the problem and how can it be solved?

You also have to add it locally by ```npm install compute-pcorr```. I tried and it worked. — Hazik Arshad, May 17 '23 at 06:08
Does this answer your question? [NodeJS require a global module/package](https://stackoverflow.com/questions/15636367/nodejs-require-a-global-module-package) — Justinas, May 17 '23 at 06:12
Global packages are usually for things like command line tools, which after you install you get a command which can be used everywhere, like `tsc`, `pkg`, etc. For dependencies which your project depends on, i.e. the code need to be ship with your project, you install it locally. — Ricky Mo, May 17 '23 at 06:13
Have you created `package.json` using `npm init` before `npm install compute-pcorr`? — Jordy, May 17 '23 at 06:20
No, but my code is now working! package.json has been automatically created and populated. — rnso, May 17 '23 at 06:24

sachin · Accepted Answer · 2023-05-17T06:14:11.007

1

This issue happens when the library is not installed locally.
Try installing locally in your directory with the command npm install compute-pcorr
There's no need of installing globally via -g

edited May 17 '23 at 06:14

answered May 17 '23 at 06:11

sachin

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You can delete this comment as it is now in your answer! – rnso May 17 '23 at 06:23
Please check all post and don't add what is already there. – Hazik Arshad May 17 '23 at 07:16

Why this package installed by npm is not found

1 Answers1