It has been suggested to me that I come and introduce myself.

Hello! I'm dduce. 

I'm a very novice programmer. As I said in a post here, I'm not a beginner, but I'm far from being a novice.

Currently, I am pursuing a degree in Chem. Engineering. I mainly program using MATLAB, as this is the program that my school has deemed a must for all engineers. Recently, I've begun programming the nspire cas for help in these upper level classes, which led me here.

Thus far, I'm very glad that I found the board.

Thanks everyone!

For displaying all of the values, I think a for loop would be best.  I am not 100% sure that this will work with an array of more than one dimension (and I can't test now ).

Code: [Select]

For x,1,dim(mstm)
Disp mstm[x][3]
EndFor

For the string issue, do you want to find the index of a certain substring in a string?

First, to convert from a number to string, use "string(number)" and to do the opposite, use "expr(string)"
To find the index of a substring in a string, use "inString(string,substring)", which will return the index of the substring if it is in the string (with the first index being "1", not "0").

I tried playing with the for loop, but it errors out, say "Domain Error". And it highlights the "mstm[ x][ 3]". I've tried mstm[x,3] , and that returns everything. The problem appears to be with way you tell the calc "all", there must be a symbol which means "all" when referencing the row... Very frustrating. Arg! 


I did figure out this:
{xx,yy}=dim(mstm)
Returns:
{xx=3,yy=64}

However, the values xx and yy are not stored as a variable. So when I type "xx" in the calc prompt, it displays "xx" and not 3. Any ideas how to fix this? I tried {xx,yy}:= , with the colon, but it doesn't like that.

Regarding the search issue. Yes, I'd like to search be able to find the index number.

Also, I used you For ... EndFor suggestion and modified it like this:
indexd:=0
While indexd<dim(ion)
indexd:=indexd+1
disp mstm[indexd]
EndWhile
But it errors too.

First, to convert from a number to string, use "string(number)" and to do the opposite, use "expr(string)"
To find the index of a substring in a string, use "inString(string,substring)", which will return the index of the substring if it is in the string ...

I'm still struggling. Sorry. Maybe an example might help: my string value, for example are: "Br" , "Ag" , and "Cl", and these reside in the ion portion of the newly created matrix/list named mstm, and there are 2 other lists which correspond each ion. These lists are charge (row2) and size (row3). An example, let's say "Ag" is the second value of row 1, but lets pretend I don't know it's the second value of row 1. Lets say I write a program that asks you to enter a string value for the ion which you are searching for, the request is stored in the variable "ur_ion".

So the idea now is to compare ur_ion with row 1 of mstm, find that strings index, then using that index # it will grab the corresponding charge and size values associated with it, and create new variables storing the charge (named: nwchrg) and size (named: nwsznm)

Using those variables the calculation will continue. The program will request input, and so on...

Maybe instring, string, and expr are what I need to be using, but I still can't seem to figure it out.

Thanks again for the help.

Ah ok. OS 2.1 should have most recent functions then. As for the BASIC language, it is more like the TI-89, but it is much more limited. Basically it doesn't have Getkey, Pixel-On/Off, Line() and Output/Text/Locate() equivalents, so the language is not suitable for people who are using their calculator for other purposes than school (such as gaming).

EDIT: Your post vanished

Sorry about that. I didn't realize apcalc had posted as well. I wanted to reply to both.

I did run across the TI89 for dummies book. I tried to follow what was going on, but the 89 is so different than the nspire, I was lost to say the least.

What do you mean that the language is a lot more limited? Is there a way to fix this?

Hello everyone! This is my first post, and first time finding the board. I'm glad to have found you all. Hopefully I can find some answers here.

About me:
I'm a Chemical Engineering student. I'm fairly familiar with programming in MATLAB, and I've been programming on the Nspire CAS for about a month steady now. I'm not a complete beginner, but I'm far from a novice.

Anyway, as I said, I have many questions that I will be posting on my journey, and hopefully I can answer a few questions too. Please, if you have any Chemistry questions, or the like, feel free to ask away. As for programming....

About the program:
I am developing a very sophisticated program that will collect strings and values, ultimately plugging these values into tons of equations and displaying answers, activities, equations, and loads more of helpful calculations and features that will help other colleagues in my field.

One problem that I am having is, you'll see the variables here, ion - charge - sznm. These are values that are stored in a spread sheet, and the headings of the columns, are the same as the variable names (as I'm sure you're all aware... just trying to be as specific as possible):

mstm:={ion,charge,sznm}

This works perfectly. If I type mstm[3], on the calculator application, for example, and press enter, the 3rd row of the matrix is displayed. Likewise, if I type in the calc promt: mstm[1,1]    , it will display the value in row one, column one. Works perfect. Now, here's the question, how do I tell it to display "ALL" rows of column 3? In MATLAB you would say mtsm(:,3) , meaning all rows in the 3rd column...

Another question that I have: is there a way to do a search for a string and/or a value?

InString and Frequency, unless I'm doing it wrong, don't appear to be what I need in order to perform this task.

in MATLAB it's a simple "find" command, and in excel, I believe it's Vlookup or Hlookup, meaning vertical/horizontal lookup, if that helps anyone.



Another question: is anyone familiar with the "indirection operator"?

I'm curious if I were to have string values stored in a list, is there a way to write a while loop, for example, that would grab each string value and convert it to a variable?


I've searched for days for this answer, which led me here. Can you help? Please  Much appreciation.