Member Avatar for DavidB

Hi, folks.

I have written some pretty complicated programs in Javascript (in terms of the code itself), but I haven’t experimented much with the nuts-and-bolts of Javascript. In particular, I have written all my programs as single blocks of code. For example, I have written several programs to solve for the eigenvalues and eigenvectors of matrices. One page solves for a 3 x 3 matrix, one for a 4 x 4 matrix, one for a 5 x 5 matrix, etc. Each javascript program is on its own page and takes the following form:

<script language="javascript" type="text/javascript">
<!--Define JavaScript function.-->

function OneBigProgram(dataForm){

// Code to input the matrix elements for the specifically-sized matrix

 . . .

// Code to calculate the eigenvalues and eigenvectors
// BIG BLOCK OF CODE
. . .

// Code to output the results for the specifically-sized matrix
 . . . 

// end of JavaScript-->
</script>

The algorithm for actually calculating the eigenvalues and eigenvectors does not change depending upon matrix size, it is included in the BIG BLOCK OF CODE.

What I am hoping to do now is turn the code block for the BIG BLOCK OF CODE into an external file, and have the several programs refer to it. That way, I won't have six programs include the same big block of code; they can all refer to the same external file--saving space on the server. For example:

<script language="javascript" type="text/javascript">
<!--Define JavaScript function.-->

function A_Smaller_Program_Input(dataForm){

// Code to input the matrix elements for the specifically-sized matrix

 . . .

// end of JavaScript-->
</script>
<script language="javascript" type="text/javascript" src="RoutineforEigenvalues.js">
</script>
function A_Smaller_Program_Output(dataForm){

// Code to output the results for the specifically-sized matrix

 . . .

// end of JavaScript-->
</script>

Is what I want to do possible? How seamlessly does Javascript transmit data between seemingly independent code blocks?

  • 3 Contributors
  • 2 Replies
  • 275 Views
  • 4 Years Discussion Span
  • Latest Post Latest Post by goldentuna
Member Avatar for hielo

You have the right syntax. Just save your program as eigenValues3.js and then if you want to write a program that needs that file you just "import" it as follows:

<html>
<head>
<script type="text/javascript" src="eigenValue3.js"></script>
<script type="text/javascript">
//The code that will use the functions in eigenValue3.js goes here
</script>
</head>
<body>...
</body>
</html>

Note: 1. You do not have to do the "import" within the <head> tag. It could have done withing the <body> tag.
2. <script> tags that are used to import files cannot enclose javascript code (or at least this was the case last time I tested this about 1yr ago). That's why I have two <script> tags above. The first one to import the file. The second to write my code for my local/current page.
3. You do not need language="javascript". Providing type="text/javascript" will suffice.

Member Avatar for goldentuna

thanks for the help on this.

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