Hello
Is complex number arithmetic possible in FPC? Another post recommends use unit so named ucomplex, but i can't find any detailed information of this in the documentation. But, amazingly, i sucessfully probed this small program:

PROGRAM DUMMY;
USES UCOMPLEX;
VAR
x,y, z, w: COMPLEX;
BEGIN
x := 8+i*7;
y := 4-5*i;
z := x+y;
w := x*y
END.

This program compile and run right, but why? I need to know about anything subroutines that works with complex numbers. It is posibble to write math operations like FORTRAN?

Thanks

The unit ucomplex is part of the rtl. It uses simple operator overloading to add a pretty useful complex type into your program. You can use it(pretty much) as any other type. It's not any special type, it's just a record where all the operators got overloaded

Try to open the source code for that unit, and you'll see how beautifully simple it is :)

Hi,

I'm trying to read and write ascii characters using FPC. I had no problems doing this years ago with Think Pascal & Code Warrior.

For some reason I'm not able to read and write ascii characters above ascii 127 with FPC. Can someone explain this to me?

Thanks in advance!

Using this code:
	for i:= 33 to 226 do
		writeln('Character: ', chr(i), '   Ascii value: ', i:1);

Character: ! Ascii value: 33
Character: " Ascii value: 34
Character: # Ascii value: 35
Character: $ Ascii value: 36
Character: % Ascii value: 37
Character: & Ascii value: 38
Character: ' Ascii value: 39
Character: ( Ascii value: 40
Character: ) Ascii value: 41
Character: * Ascii value: 42
Character: + Ascii value: 43
Character: , Ascii value: 44
Character: - Ascii value: 45
Character: . Ascii value: 46
Character: / Ascii value: 47
Character: 0 Ascii value: 48
Character: 1 Ascii value: 49
Character: 2 Ascii value: 50
Character: 3 Ascii value: 51
Character: 4 Ascii value: 52
Character: 5 Ascii value: 53
Character: 6 Ascii value: 54
Character: 7 Ascii value: 55
Character: 8 Ascii value: 56
Character: 9 Ascii value: 57
Character: : Ascii value: 58
Character: ; Ascii value: 59
Character: < Ascii value: 60
Character: = Ascii value: 61
Character: > Ascii value: 62
Character: ? Ascii value: 63
Character: @ Ascii value: 64
Character: A Ascii value: 65
Character: B Ascii value: 66
Character: C Ascii value: 67
Character: D Ascii value: 68
Character: E Ascii value: 69
Character: F Ascii value: 70
Character: G Ascii value: 71
Character: H Ascii value: 72
Character: I Ascii value: 73
Character: J Ascii value: 74
Character: K Ascii value: 75
Character: L Ascii value: 76
Character: M Ascii value: 77
Character: N Ascii value: 78
Character: O Ascii value: 79
Character: P Ascii value: 80
Character: Q Ascii value: 81
Character: R Ascii value: 82
Character: S Ascii value: 83
Character: T Ascii value: 84
Character: U Ascii value: 85
Character: V Ascii value: 86
Character: W Ascii value: 87
Character: X Ascii value: 88
Character: Y Ascii value: 89
Character: Z Ascii value: 90
Character: [ Ascii value: 91
Character: \ Ascii value: 92
Character: ] Ascii value: 93
Character: ^ Ascii value: 94
Character: _ Ascii value: 95
Character: ` Ascii value: 96
Character: a Ascii value: 97
Character: b Ascii value: 98
Character: c Ascii value: 99
Character: d Ascii value: 100
Character: e Ascii value: 101
Character: f Ascii value: 102
Character: g Ascii value: 103
Character: h Ascii value: 104
Character: i Ascii value: 105
Character: j Ascii value: 106
Character: k Ascii value: 107
Character: l Ascii value: 108
Character: m Ascii value: 109
Character: n Ascii value: 110
Character: o Ascii value: 111
Character: p Ascii value: 112
Character: q Ascii value: 113
Character: r Ascii value: 114
Character: s Ascii value: 115
Character: t Ascii value: 116
Character: u Ascii value: 117
Character: v Ascii value: 118
Character: w Ascii value: 119
Character: x Ascii value: 120
Character: y Ascii value: 121
Character: z Ascii value: 122
Character: { Ascii value: 123
Character: | Ascii value: 124
Character: } Ascii value: 125
Character: ~ Ascii value: 126
Character: Ascii value: 127
Character: ? Ascii value: 128
Character: ? Ascii value: 129
Character: ? Ascii value: 130
Character: ? Ascii value: 131
Character: ? Ascii value: 132
Character: ? Ascii value: 133
Character: ? Ascii value: 134
Character: ? Ascii value: 135
Character: ? Ascii value: 136
Character: ? Ascii value: 137

truncated for brevity.

Thomas Young
mobile email:

Hi,

I'm trying to read and write ascii characters using FPC. I had no problems doing this years ago with Think Pascal & Code Warrior.

For some reason I'm not able to read and write ascii characters above ascii 127 with FPC. Can someone explain this to me?

Thanks in advance!

Using this code:
	for i:= 33 to 226 do
		writeln('Character: ', chr(i), '   Ascii value: ', i:1);

Character: ! Ascii value: 33
Character: " Ascii value: 34
Character: # Ascii value: 35
Character: $ Ascii value: 36
Character: % Ascii value: 37
Character: & Ascii value: 38
Character: ' Ascii value: 39
Character: ( Ascii value: 40
Character: ) Ascii value: 41
Character: * Ascii value: 42
Character: + Ascii value: 43
Character: , Ascii value: 44
Character: - Ascii value: 45
Character: . Ascii value: 46
Character: / Ascii value: 47
Character: 0 Ascii value: 48
Character: 1 Ascii value: 49
Character: 2 Ascii value: 50
Character: 3 Ascii value: 51
Character: 4 Ascii value: 52
Character: 5 Ascii value: 53
Character: 6 Ascii value: 54
Character: 7 Ascii value: 55
Character: 8 Ascii value: 56
Character: 9 Ascii value: 57
Character: : Ascii value: 58
Character: ; Ascii value: 59
Character: < Ascii value: 60
Character: = Ascii value: 61
Character: > Ascii value: 62
Character: ? Ascii value: 63
Character: @ Ascii value: 64
Character: A Ascii value: 65
Character: B Ascii value: 66
Character: C Ascii value: 67
Character: D Ascii value: 68
Character: E Ascii value: 69
Character: F Ascii value: 70
Character: G Ascii value: 71
Character: H Ascii value: 72
Character: I Ascii value: 73
Character: J Ascii value: 74
Character: K Ascii value: 75
Character: L Ascii value: 76
Character: M Ascii value: 77
Character: N Ascii value: 78
Character: O Ascii value: 79
Character: P Ascii value: 80
Character: Q Ascii value: 81
Character: R Ascii value: 82
Character: S Ascii value: 83
Character: T Ascii value: 84
Character: U Ascii value: 85
Character: V Ascii value: 86
Character: W Ascii value: 87
Character: X Ascii value: 88
Character: Y Ascii value: 89
Character: Z Ascii value: 90
Character: [ Ascii value: 91
Character: \ Ascii value: 92
Character: ] Ascii value: 93
Character: ^ Ascii value: 94
Character: _ Ascii value: 95
Character: ` Ascii value: 96
Character: a Ascii value: 97
Character: b Ascii value: 98
Character: c Ascii value: 99
Character: d Ascii value: 100
Character: e Ascii value: 101
Character: f Ascii value: 102
Character: g Ascii value: 103
Character: h Ascii value: 104
Character: i Ascii value: 105
Character: j Ascii value: 106
Character: k Ascii value: 107
Character: l Ascii value: 108
Character: m Ascii value: 109
Character: n Ascii value: 110
Character: o Ascii value: 111
Character: p Ascii value: 112
Character: q Ascii value: 113
Character: r Ascii value: 114
Character: s Ascii value: 115
Character: t Ascii value: 116
Character: u Ascii value: 117
Character: v Ascii value: 118
Character: w Ascii value: 119
Character: x Ascii value: 120
Character: y Ascii value: 121
Character: z Ascii value: 122
Character: { Ascii value: 123
Character: | Ascii value: 124
Character: } Ascii value: 125
Character: ~ Ascii value: 126
Character: Ascii value: 127
Character: ? Ascii value: 128
Character: ? Ascii value: 129
Character: ? Ascii value: 130
Character: ? Ascii value: 131
Character: ? Ascii value: 132
Character: ? Ascii value: 133
Character: ? Ascii value: 134
Character: ? Ascii value: 135
Character: ? Ascii value: 136
Character: ? Ascii value: 137

truncated for brevity.

Thomas Young
mobile email:

The world has changed, and globalization has reached your computer. Your computer is almost definitely using a different character set today than it was back in those days long ago. read this:
http://www.joelonsoftware.com/articles/Unicode.html The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!)

~D.

In our previous episode, Thomas Young said:

For some reason I'm not able to read and write ascii characters above ascii 127 with FPC. Can someone explain this to me?

This is very logical, since ASCII only defines +/- 127 chars.

The upper 128 were used for vendor specific characters (aka codepages), which were later somewhat standarized in ISO norms.

So the first step is what characters you actualy expect above 127.

Thank you for the article. It was very helpful.

Why is it I can read and write a string that contains characters in the upper 128 but can't read & write them as individual char?

Specifically I need to read the copyright (169), trademark (170) and registration (168) characters. Any suggestions on how I can do this?

Thomas Young
cell: 330-256-7064
mobile email:

This is most probably due to the fact that your platform uses/requires a multi-byte encoding of these characters nowadays (probably UTF-8) as opposed to the platform / version you used those 'years ago' with ThinkPascal. You need a different way for referring to the particular characters than you used in the past, or you need to translate the original meaning (based on a particular character set like Mac Roman you may have used in the past).

Specifically I need to read the copyright (169), trademark (170) and registration (168) characters. Any suggestions on how I can do this?

If you specifically need these, put those characters as constant strings in your code and use those strings. Also, make sure to specify the encoding used for your source code directly in the source code (using the respective compiler directive or the UTF-8 marker) to avoid possible wrong interpretation.

Tomas

.
.

Thanks! I recently downloaded the rtl source code, and confirmed this

2011/10/5 Jeppe Græsdal Johansen