Services & ResourcesWolfram ForumsMathGroup Archive

[Date Index] [Thread Index] [Author Index]

Multiplying a constant to a matrix column

• To: mathgroup at smc.vnet.net
• Subject: [mg16251] Multiplying a constant to a matrix column
• From: "Hyo Ahn" <heahn at nanum.kaeri.re.kr>
• Date: Fri, 5 Mar 1999 00:41:15 -0500
• Organization: Korea Atomic Energy Research Institute
• Sender: owner-wri-mathgroup at wolfram.com

Hi,

I would like to multiply a constant number to a given column of an existing
matrix in Mathematica and I am having a hard time.

First, I have a 1000 x 3 matrix A.  There is no command that allow me to
multiply a constant number to a specific column, so I extract three columns
separately using

A1 = A[Range[1,1000],Range[1,1]];
A2 = A[Range[1,1000],Range[2,2]];
A3 = A[Range[1,1000],Range[3,3]];

fpr the first column and so on.  Then I multiply a constant to a extracted
column which is a vector now.   Finally, I tried

A4 = ColumnJoin[A1,A2,A3]

but I found out that ColumnJoin command does not worked the way I expected
it to be.

Could anyone know a simple solution to this problem?

Thanks.

Hyo Ahn
KAERI

• Follow-Ups:
  • Re: Multiplying a constant to a matrix column
    • From: Mitch Stonehocker <derivado@campus.ccm.itesm.mx>
  • Re: Multiplying a constant to a matrix column
    • From: Jurgen Tischer <jtischer@col2.telecom.com.co>