Mathcad 15- How can I get custom units to work?

[rmarshall]

I am new to mathcad. As I understand the instructions, custom units should work with in a worksheet. The following entries do not work.

I will appreciate any help I can get.

Ron Marshall

[MikeArmstrong]

Try this.

Mike

[RichardJ]

As Mike syas, get rid of the 1 on the LHS of the assignment. That is not allowed.

[rmarshall]

Thanks for the suggestions. I have tried several variations. I retried removing the 1, but Mathcad will not recognize amu as a unit so far.

[MikeArmstrong]

It will, look at my example posted above. That was created in M15.

Mike

[RichardJ]

Please post a worksheet (to do this, click on "advanced editor" at the top right of the edit dialogue) showing the problem. We need that to figure out where your problem lies.

[rmarshall]

I have attached the worksheet as an xmcd file.

Ron Marshall

[wayne]

You typed something incorrectly when you entered (or modified) the RHS for amu, just re-type the definition.

[RichardJ · Accepted solution]

You have two typographical problems. First, immediately in front of the 10 is a space. I don't know how you got that, but it means Mathcad thinks <space>10 is a variable. The second one is really bizarre. I can't even figure out how to create it. Select the kg with the insertion point to the right. then delete the kg by backspacing, and finally delete the multiplication operator. You will see that the entire expression is surrounded by parentheses: (amu:=1.66053886*10^27). So somehow it's grouped the LHS and the RHS. I don't know how to do that even if I wanted to . It must be the result of some sequence of edits you did, probably involving the "1" that was originally on the LHS.

The solution is just to delete the entire expression and retype it.

[rmarshall]

I have been copying and pasting numbers. I have noticed when I type in a whole line things seem to work the first time, what looks like straight foward editing seems to lead to problems. Your solution worked. Thanks to both of you.

Ron Marshall

[RichardJ]

When you select something be careful what you are selecting. Watch that blue line

[ValeryOchkov]

The amu is a built-in unit (constant) in Mathcad Prime: