# Finite element nodes

**URL:** <https://community.freefem.org/t/finite-element-nodes/1701>\
**Category:** General Discussion\
**Created:** [April 26, 2022, 1:44pm UTC](https://community.freefem.org/t/finite-element-nodes/1701 "2022-04-26T13:44:22Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Qianrui](https://avatars.discourse-cdn.com/v4/letter/q/9fc348/32.png) [@Qianrui](https://community.freefem.org/u/Qianrui)\
**Post date:** [April 26, 2022, 1:44pm UTC](https://community.freefem.org/t/finite-element-nodes/1701/1 "2022-04-26T13:44:23Z")

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Hello, can freefem + + store finite element nodes instead of mesh nodes?

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**Author:** ![frederichecht](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/frederichecht/32/15_2.png) [@frederichecht](https://community.freefem.org/u/frederichecht)\
**Post date:** [April 26, 2022, 5:20pm UTC](https://community.freefem.org/t/finite-element-nodes/1701/2 "2022-04-26T17:20:26Z")

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The question is not clear for my.

the node in freefem is the support of the degree of freefem

in 2d the node could be : vertex, edge , or element.  
so you have 7 kinds of nodes

but you can have more than one dof one node.

the numbering of dof in on element is basis  
start with dof on vertex 0, dof on vertex 1, dof on vertex 2, dof on edge 0, …

if Wh is a FEpase on TH  
Wh(k,i) = number of dof i in element k.

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<div class="post-metadata">

**Author:** ![Qianrui](https://avatars.discourse-cdn.com/v4/letter/q/9fc348/32.png) [@Qianrui](https://community.freefem.org/u/Qianrui)\
**Post date:** [April 27, 2022, 9:16am UTC](https://community.freefem.org/t/finite-element-nodes/1701/3 "2022-04-27T09:16:42Z")

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thankyou very much. Using the following commands,

> savemesh(Th);

the coordinates of grid nodes and boundary information are output, but with P2 element, each element needs six finite element nodes, and the information of the other three nodes is not output.

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<div class="post-metadata">

**Author:** ![frederichecht](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/frederichecht/32/15_2.png) [@frederichecht](https://community.freefem.org/u/frederichecht)\
**Post date:** [May 1, 2022, 1:43pm UTC](https://community.freefem.org/t/finite-element-nodes/1701/4 "2022-05-01T13:43:18Z")

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If you need the coordinate of P2 nodes

```auto
       fespace Vh(Th,P2);
       Vh X=x, Y=y;

```

The array X[], and Y[] gives the coordinate of the P2 node.