50g EVAL keyboard function
2012-02-20 by pin224466
I'm a new 50G user and have a question regarding the use of EVAL and how/where the function looks for variable substitution in the calculator.
1. While learning the calculator, I made a couple of simple named variables in the 'home' directory. The variables were named 'A' and 'D'. These variables were never deleted from my 'home' directory.
2. in the '50g users guide' on page 6-21 (this is the big 9MB guide HP part number F2229AA-90006), Example 3 "Flow in a Pipe", there is an exercise for inputing formulas with some portions of the equations existing in separate variables. One of the final steps of the exercise is to use the 'EVAL' keyboard function to combined the variables into a single equation.
3. I input the formulas using the names exactly as defined in the users guide in a SEPARATE directory as the exercise defines. The directory is called 'PIPES'.
4. One of the exercises variables is named 'A' and has, as part of it's equation a variable named 'D'.
Upon executing the 'EVAL function, the calculator showed an error.
After some thought, I realized that, even though the calculator was set to the 'PIPES' directory, and the primary equation that was being 'EVAL'd was in the 'PIPES' and all the variable based equations that were to be substituted into the primary equation were in the 'PIPES directory, the calculator was looking back into the 'home' directory and trying to substitue for the variable 'D' that existed there.
My question is this... how do you make the 50g focus on local named variables defined in a subdirectory for functions like 'EVAL', programs, etc.
I can't imagine having to remember every variable created and stored on this calculator so that when future programs are written, they won't mistakenly fill in the wrong information.
thanks....
1. While learning the calculator, I made a couple of simple named variables in the 'home' directory. The variables were named 'A' and 'D'. These variables were never deleted from my 'home' directory.
2. in the '50g users guide' on page 6-21 (this is the big 9MB guide HP part number F2229AA-90006), Example 3 "Flow in a Pipe", there is an exercise for inputing formulas with some portions of the equations existing in separate variables. One of the final steps of the exercise is to use the 'EVAL' keyboard function to combined the variables into a single equation.
3. I input the formulas using the names exactly as defined in the users guide in a SEPARATE directory as the exercise defines. The directory is called 'PIPES'.
4. One of the exercises variables is named 'A' and has, as part of it's equation a variable named 'D'.
Upon executing the 'EVAL function, the calculator showed an error.
After some thought, I realized that, even though the calculator was set to the 'PIPES' directory, and the primary equation that was being 'EVAL'd was in the 'PIPES' and all the variable based equations that were to be substituted into the primary equation were in the 'PIPES directory, the calculator was looking back into the 'home' directory and trying to substitue for the variable 'D' that existed there.
My question is this... how do you make the 50g focus on local named variables defined in a subdirectory for functions like 'EVAL', programs, etc.
I can't imagine having to remember every variable created and stored on this calculator so that when future programs are written, they won't mistakenly fill in the wrong information.
thanks....