drawLineRelative

[philtong]

In the following code, why is it that the High/Low lines are drawn only once for the last bar? It seems that it would do it for every bar. (It does what I want but I don't understand). Thanks.

function preMain() {
setPriceStudy(true);
}

var vtime
var vHigh;
var vLow;
var BarCntr = 0;
function main() {


if (getBarState() == BARSTATE_NEWBAR) {
BarCntr +=1;

vHigh = high();
vLow = low();
debugPrint("Bar=" + BarCntr + " Max=" + vHigh + " Min=" + vLow + "\n");

for (i = 0; i < 20; ++i) {
vHigh = Math.max(high(-i), vHigh);
vLow = Math.min(low(-i), vLow);
}

drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "High");
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "Low");
}

}

[dloomis]

try this

drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "High",bar);
bar=+1
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "Low"bar);

[philtong]

invalid number of arguments

i get "invalid number of arguments". what was it supposed to do?

code:
var bar;
...
drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "High", bar);
bar=+1
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "Low", bar);
...

[gspiker]

The problem you are seeing is due to the fact that the label is supposed to be unique for each line. If it isn't, then only the last line with that label will be seen.

Try this:

var bar=0;

drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "High", "H" + bar);
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "Low", "L" + bar);
bar++;

[philtong]

Actually,
drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "High", "H" + bar);
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "Low", "L" + bar);

was still causing "Invalid number of parameters" error. So I changed it to:

drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "H" + bar);
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "L" + bar);

figuring that the last parameter must be the "Label" you are talking about.

The "invalid number of parameters" error is gone but it remains that the high/low bars are printed only once for the last bar. I'd like to understand this so that in case I do want to draw multiple bars, I can. Thanks.

[dloomis]

http://www.esignalcentral.com/training/esignal/advcharting/Text.asp

says

drawLineRelative(x1, y1, x2, y2, style, thickness, color);
drawLineAbsolute(x1, y1, x2, y2, style, thickness, color);

Style
PS_SOLID
PS_DASH
PS_DOT
PS_DASHDOT
PS_DASHDOTDOT

Thickness
Thickness of line. Minimum of 1.

Color

Color.RGB or Color.colorname

Is it possible this is leaving out some of the parameters?

[eSignal_JasonK]

Hello philtong,

Welcome to the Boards. Here's a link to the current specs for this function.

Drawing Images, Shapes, and Text with EFS

[gspiker]

Originally posted by philtong
Actually,
drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "High", "H" + bar);
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "Low", "L" + bar);

was still causing "Invalid number of parameters" error. So I changed it to:

drawLineRelative(-20, vHigh, 0, vHigh, PS_SOLID, 2, Color.red, "H" + bar);
drawLineRelative(-20, vLow, 0, vLow, PS_SOLID, 2, Color.green, "L" + bar);

Yes, sorry I wrote that really quickly before heading out on my adventures. That is the correct way.

I'd like to understand this so that in case I do want to draw multiple bars, I can. Thanks.

Again my fault. Move bar to be defined outside both main() and preMain() so it's value is maintained through each iteration of main()

preMain(){
}

var bar = 0;

main(){

.
.
.
}

As long as you increment bar (bar++) after the drawline commands you should be fine.