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got a problem with variables and setting values

r.d. terramir

Sun, Apr 29, 2018 2:27 AM

here's my code I wanted to make the code parametric so I needed
various possible values but I hit a snag.

bearings=10;
//for smooth rods put in diameter in mm
smooth=10;
// for z-screw 5 for 5mm 8 for 8mm and 8.5 for acme
z_screw=5;
// for mechanical z=probe use 1 for yes 0 for no 2 for i3 type probe
z_probe = 1;
wall=4;
lmd=1;
lml=1;
echo(bearings,smooth,z_screw);
if (bearings==10){lmd=19.05;lml=29.05;}
echo(lmd,lml);

lmd and lml return 1 even though I thought I was assigning the actual
values with the if statement.

Respectfully,
R. Daniel Borkan
727 S. Coronado St. 201
Los Angeles, CA 90057
C: (213) 271-6721
All written content of this e-mail is confidential and only intended for
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here's my code I wanted to make the code parametric so I needed various possible values but I hit a snag. bearings=10; //for smooth rods put in diameter in mm smooth=10; // for z-screw 5 for 5mm 8 for 8mm and 8.5 for acme z_screw=5; // for mechanical z=probe use 1 for yes 0 for no 2 for i3 type probe z_probe = 1; wall=4; lmd=1; lml=1; echo(bearings,smooth,z_screw); if (bearings==10){lmd=19.05;lml=29.05;} echo(lmd,lml); lmd and lml return 1 even though I thought I was assigning the actual values with the if statement. Respectfully, R. Daniel Borkan 727 S. Coronado St. 201 Los Angeles, CA 90057 C: (213) 271-6721 All written content of this e-mail is confidential and only intended for the named recipient. This message is subject to copyright and is intellectual property of the sender. All rights reserved (c) 2018

Jordan Brown

Sun, Apr 29, 2018 2:38 PM

On 4/28/2018 7:27 PM, r.d. terramir wrote:

here's my code I wanted to make the code parametric so I needed
various possible values but I hit a snag.

lmd and lml return 1 even though I thought I was assigning the actual
values with the if statement.

This might well be the most common OpenSCAD question.

OpenSCAD variables... aren't variables. They're constants, sort of,
with the last assignment winning and with inner scopes able to override
values from outer scopes. You can't change them, or at least not
exactly, and you especially can't change them inside an "if".

x=1;
echo(x=x);
x=2;
echo(x=x);

produces

ECHO: x = 2
ECHO: x = 2

and

x=1;
echo(x=x);
if (true) {
    x=2;
    echo (x=x);
}
echo (x=x);

produces

ECHO: x = 1
ECHO: x = 2
ECHO: x = 1

For your case here, you need to use the ?: operator to set the right
value when you do the initial assignment.

lmd= bearings==10 ? 19.05 : 1;
lml= bearings==10 ? 29.05 : 1;
echo(bearings,smooth,z_screw);
echo(lmd,lml);

On 4/28/2018 7:27 PM, r.d. terramir wrote: > here's my code I wanted to make the code parametric so I needed > various possible values but I hit a snag. > > bearings=10; > //for smooth rods put in diameter in mm > smooth=10; > // for z-screw 5 for 5mm 8 for 8mm and 8.5 for acme > z_screw=5; > // for mechanical z=probe use 1 for yes 0 for no 2 for i3 type probe > z_probe = 1; > wall=4; > lmd=1; > lml=1; > echo(bearings,smooth,z_screw); > if (bearings==10){lmd=19.05;lml=29.05;} > echo(lmd,lml); > > lmd and lml return 1 even though I thought I was assigning the actual > values with the if statement. This might well be the most common OpenSCAD question. OpenSCAD variables... aren't variables. They're constants, sort of, with the last assignment winning and with inner scopes able to override values from outer scopes. You can't change them, or at least not exactly, and you especially can't change them inside an "if". x=1; echo(x=x); x=2; echo(x=x); produces ECHO: x = 2 ECHO: x = 2 and x=1; echo(x=x); if (true) { x=2; echo (x=x); } echo (x=x); produces ECHO: x = 1 ECHO: x = 2 ECHO: x = 1 For your case here, you need to use the ?: operator to set the right value when you do the initial assignment. lmd= bearings==10 ? 19.05 : 1; lml= bearings==10 ? 29.05 : 1; echo(bearings,smooth,z_screw); echo(lmd,lml);