I'm new here and i want to ask about my work. So I'm using this code for now but result is shown only full horizontal line not from the high from highestbars . How can i draw from exact highest price?
And im using time.session like "0000-0500" but this session in 1 exchange (broker)is different from other
exchanges. So how can I use same Session?
high = security(syminfo.tickerid, 'D', time[1], lookahead = barmerge.lookahead_on)
prevhigh = security(syminfo.tickerid, 'D', high[1], lookahead = barmerge.lookahead_on)
var high_line = line.new(x1 = high, x2 = right(extend_right), y1 = prevhigh, y2 = prevhigh, color = line_color, width = line_width, xloc = xloc.bar_time)
line.set_x1(high_line, high)
And can i fill between 2 lines which drawn by above code?
i used Line.set
Thank you.
Pine editor still does not have built-in functions to plot lines (such as support lines, trend lines).
I could not find any direct or indirect method to draw lines.
I want to build function that look like below (for example only)
draw_line(price1, time1,price2, time2)
any Ideas or suggestions ?
Unfortunately I don't think this is something they want to provide. Noticing several promising posts from 4 years ago that never came through. The only other way, seem to involve some calculations, by approximating your line with some line plots, where you hide the non-relevant parts.
For example:
...
c = close >= open ? lime : red
plot(close, color = c)
would produce something like this:
Then, you could try to replace red with na to get only the green parts.
Example 2
I've done some more experiments. Apparently Pine is so crippled you can't even put a plot in function, so the only way seem to be to use the point slope formula for a line, like this:
//#version=3
study(title="Simple Line", shorttitle='AB', overlay=true)
P1x = input(5744)
P1y = input(1.2727)
P2x = input(5774)
P2y = input(1.2628)
plot(n, color=na, style=line) // hidden plot to show the bar number in indicator
// point slope
m = - (P2y - P1y) / (P2x - P1x)
// plot range
AB = n < P1x or n > P2x ? na : P1y - m*(n - P1x)
LA = (n == P1x) ? P1y : na
LB = (n == P2x) ? P2y : na
plot(AB, title="AB", color=#ff00ff, linewidth=1, style=line, transp=0)
plotshape(LA, title='A', location=location.absolute, color=silver, transp=0, text='A', textcolor=black, style=shape.labeldown)
plotshape(LB, title='B', location=location.absolute, color=silver, transp=0, text='B', textcolor=black, style=shape.labelup )
The result is quite nice, but too inconvenient to use.
UPDATE: 2019-10-01
Apparently they have added some new line functionality to Pinescript 4.0+.
Here is an example of using the new vline() function:
//#version=4
study("vline() Function for Pine Script v4.0+", overlay=true)
vline(BarIndex, Color, LineStyle, LineWidth) => // Verticle Line, 54 lines maximum allowable per indicator
return = line.new(BarIndex, -1000, BarIndex, 1000, xloc.bar_index, extend.both, Color, LineStyle, LineWidth)
if(bar_index%10==0.0)
vline(bar_index, #FF8000ff, line.style_solid, 1) // Variable assignment not required
As for the other "new" line function, I have not tested it yet.
This is now possible in Pine Script v4:
//#version=4
study("Line", overlay=true)
l = line.new(bar_index, high, bar_index[10], low[10], width = 4)
line.delete(l[1])
Here is a vertical line function by midtownsk8rguy on TradingView:
vline(BarIndex, Color, LineStyle, LineWidth) => // Verticle Line Function, ≈50-54 lines maximum allowable per indicator
// return = line.new(BarIndex, 0.0, BarIndex, 100.0, xloc.bar_index, extend.both, Color, LineStyle, LineWidth) // Suitable for study(overlay=false) and RSI, Stochastic, etc...
// return = line.new(BarIndex, -1.0, BarIndex, 1.0, xloc.bar_index, extend.both, Color, LineStyle, LineWidth) // Suitable for study(overlay=false) and +/-1.0 oscillators
return = line.new(BarIndex, low - tr, BarIndex, high + tr, xloc.bar_index, extend.both, Color, LineStyle, LineWidth) // Suitable for study(overlay=true)
if(bar_index%10==0.0) // Generically plots a line every 10 bars
vline(bar_index, #FF8000ff, line.style_solid, 1) // Variable assignment not required
You can also use if barstate.islast if you only draw your lines once instead of on each candle, this way you don't need to delete the previous lines.
More compact code for draw lines:
//#version=3
study("Draw line", overlay=true)
plot(n, color=na, style=line)
AB(x1,x2,y1,y2) => n < x1 or n > x2 ? na : y1 + (y2 - y1) / (x2 - x1) * (n - x1)
plot(AB(10065,10136,3819,3893), color=#ff00ff, linewidth=1, style=line,
transp=0)
plot(AB(10091,10136,3966.5,3931), color=#ff00ff, linewidth=1, style=line,
transp=0)
Here is an example that might answer the original question:
//#version=4
study(title="trendline example aapl", overlay=true)
//#AAPL
line12= line.new(x1=int(1656322200000),
y1=float(143.49),
x2=int(1659519000000),
y2=float(166.59),
extend=extend.right,
xloc=xloc.bar_time)
(to calculate the time it needs to be calculated as the *bar open time in unix milliseconds see: https://currentmillis.com/ ; can be calculated in excel with this formula =
= (([date eg mm/dd/yyyy]+[bar open time eg 9.30am])- 0/24 - DATE(1970,1,1)) * 86400000
= ((6/27/2022+9:30:00 AM)- 0/24 - DATE(1970,1,1)) * 86400000
= ((44739+0.395833333333333)- 0/24 - DATE(1970,1,1)) * 86400000
= 1656322200000
)
adjust the zero/24 to offset the time zone if needed eg 1/24
I want to animate a sprite from point y1 to point y2 with some sort of deceleration. when it reaches point y2, the speed of the object will be 0 so it will completely stop.
I Know the two points, and I know the object's starting speed.
The animation time is not so important to me. I can decide on it if needed.
for example: y1 = 0, y2 = 400, v0 = 250 pixels per second (= starting speed)
I read about easing functions but I didn't understand how do I actually implement it in the
update loop.
here's my update loop code with the place that should somehow implement an easing function.
-(void)onTimerTick{
double currentTime = CFAbsoluteTimeGetCurrent() ;
float timeDelta = self.lastUpdateTime - currentTime;
self.lastUpdateTime = currentTime;
float *pixelsToMove = ???? // here needs to be some formula using v0, timeDelta, y2, y1
sprite.y += pixelsToMove;
}
Timing functions as Bézier curves
An easing timing function is basically a Bézier curve from (0,0) to (1,1) where the horizontal axis is "time" and the vertical axis is "amount of change". Since a Bézier curve mathematically is as
start*(1-t)^3 + c1*t(1-t)^2 + c2*t^2(1-t) + end*t^3
you can insert any time value and get the amount of change that should be applied. Note that both time and change is normalized (in the range of 0 to 1).
Note that the variable t is not the time value, t is how far along the curve you have come. The time value is the x value of the point along the curve.
The curve below is a sample "ease" curve that starts off slow, goes faster and slows down in the end.
If for example a third of the time had passed you would calculate what amount of change that corresponds to be update the value of the animated property as
currentValue = beginValue + amountOfChange*(endValue-beginValue)
Example
Say you are animating the position from (50, 50) to (200, 150) using a curve with control points at (0.6, 0.0) and (0.5, 0.9) and a duration of 4 seconds (the control points are trying to be close to that of the image above).
When 1 second of the animation has passed (25% of total duration) the value along the curve is:
(0.25,y) = (0,0)*(1-t)^3 + (0.6,0)*t(1-t)^2 + (0.5,0.9)*t^2(1-t) + (1,1)*t^3
This means that we can calculate t as:
0.25 = 0.6*t(1-t)^2 + 0.5*t^2(1-t) + t^3
Wolfram Alpha tells me that t = 0.482359
If we the input that t in
y = 0.9*t^2*(1-t) + t^3
we will get the "amount of change" for when 1 second of the duration has passed.
Once again Wolfram Alpha tells me that y = 0.220626 which means that 22% of the value has changed after 25% of the time. This is because the curve starts out slow (you can see in the image that it is mostly flat in the beginning).
So finally: 1 second into the animation the position is
(x, y) = (50, 50) + 0.220626 * (200-50, 150-50)
(x, y) = (50, 50) + 0.220626 * (150, 100)
(x, y) = (50, 50) + (33.0939, 22.0626)
(x, y) = (50+33.0939, 50+22.0626)
(x, y) = (83.0939, 72.0626)
I hope this example helps you understanding how to use timing functions.
I have a question regarding the math that Apple is using in it's speak here example.
A little background: I know that average power and peak power returned by the AVAudioRecorder and AVAudioPlayer is in dB. I also understand why the RMS power is in dB and that it needs to be converted into amp using pow(10, (0.5 * avgPower)).
My question being:
Apple uses this formula to create it's "Meter Table"
MeterTable::MeterTable(float inMinDecibels, size_t inTableSize, float inRoot)
: mMinDecibels(inMinDecibels),
mDecibelResolution(mMinDecibels / (inTableSize - 1)),
mScaleFactor(1. / mDecibelResolution)
{
if (inMinDecibels >= 0.)
{
printf("MeterTable inMinDecibels must be negative");
return;
}
mTable = (float*)malloc(inTableSize*sizeof(float));
double minAmp = DbToAmp(inMinDecibels);
double ampRange = 1. - minAmp;
double invAmpRange = 1. / ampRange;
double rroot = 1. / inRoot;
for (size_t i = 0; i < inTableSize; ++i) {
double decibels = i * mDecibelResolution;
double amp = DbToAmp(decibels);
double adjAmp = (amp - minAmp) * invAmpRange;
mTable[i] = pow(adjAmp, rroot);
}
}
What are all the calculations - or rather, what do each of these steps do? I think that mDecibelResolution and mScaleFactor are used to plot 80dB range over 400 values (unless I'm mistaken). However, what's the significance of inRoot, ampRange, invAmpRange and adjAmp? Additionally, why is the i-th entry in the meter table "mTable[i] = pow(adjAmp, rroot);"?
Any help is much appreciated! :)
Thanks in advance and cheers!
It's been a month since I've asked this question, and thanks, Geebs, for your response! :)
So, this is related to a project that I've been working on, and the feature that is based on this was implemented about 2 days after asking that question. Clearly, I've slacked off on posting a closing response (sorry about that). I posted a comment on Jan 7, as well, but circling back, seems like I had a confusion with var names. >_<. Thought I'd give a full, line by line answer to this question (with pictures). :)
So, here goes:
//mDecibelResolution is the "weight" factor of each of the values in the meterTable.
//Here, the table is of size 400, and we're looking at values 0 to 399.
//Thus, the "weight" factor of each value is minValue / 399.
MeterTable::MeterTable(float inMinDecibels, size_t inTableSize, float inRoot)
: mMinDecibels(inMinDecibels),
mDecibelResolution(mMinDecibels / (inTableSize - 1)),
mScaleFactor(1. / mDecibelResolution)
{
if (inMinDecibels >= 0.)
{
printf("MeterTable inMinDecibels must be negative");
return;
}
//Allocate a table to store the 400 values
mTable = (float*)malloc(inTableSize*sizeof(float));
//Remember, "dB" is a logarithmic scale.
//If we have a range of -160dB to 0dB, -80dB is NOT 50% power!!!
//We need to convert it to a linear scale. Thus, we do pow(10, (0.05 * dbValue)), as stated in my question.
double minAmp = DbToAmp(inMinDecibels);
//For the next couple of steps, you need to know linear interpolation.
//Again, remember that all calculations are on a LINEAR scale.
//Attached is an image of the basic linear interpolation formula, and some simple equation solving.
//As per the image, and the following line, (y1 - y0) is the ampRange -
//where y1 = maxAmp and y0 = minAmp.
//In this case, maxAmp = 1amp, as our maxDB is 0dB - FYI: 0dB = 1amp.
//Thus, ampRange = (maxAmp - minAmp) = 1. - minAmp
double ampRange = 1. - minAmp;
//As you can see, invAmpRange is the extreme right hand side fraction on our image's "Step 3"
double invAmpRange = 1. / ampRange;
//Now, if we were looking for different values of x0, x1, y0 or y1, simply substitute it in that equation and you're good to go. :)
//The only reason we were able to get rid of x0 was because our minInterpolatedValue was 0.
//I'll come to this later.
double rroot = 1. / inRoot;
for (size_t i = 0; i < inTableSize; ++i) {
//Thus, for each entry in the table, multiply that entry with it's "weight" factor.
double decibels = i * mDecibelResolution;
//Convert the "weighted" value to amplitude using pow(10, (0.05 * decibelValue));
double amp = DbToAmp(decibels);
//This is linear interpolation - based on our image, this is the same as "Step 3" of the image.
double adjAmp = (amp - minAmp) * invAmpRange;
//This is where inRoot and rroot come into picture.
//Linear interpolation gives you a "straight line" between 2 end-points.
//rroot = 0.5
//If I raise a variable, say myValue by 0.5, it is essentially taking the square root of myValue.
//So, instead of getting a "straight line" response, by storing the square root of the value,
//we get a curved response that is similar to the one drawn in the image (note: not to scale).
mTable[i] = pow(adjAmp, rroot);
}
}
Response Curve image: As you can see, the "Linear curve" is not exactly a curve. >_<
Hope this helps the community in some way. :)
No expert, but based on physics and math:
Assume the max amplitude is 1 and minimum is 0.0001 [corresponding to -80db, which is what min db value is set to in the apple example : #define kMinDBvalue -80.0 in AQLevelMeter.h]
minAmp is the minimum amplitude = 0.0001 for this example
Now, all that is being done is the amplitudes in multiples of the decibel resolution are being adjusted against the minimum amplitude:
adjusted amplitude = (amp-minamp)/(1-minamp)
This makes the range of the adjusted amplitude = 0 to 1 instead of 0.0001 to 1 (if that was desired).
inRoot is set to 2 here. rroot=1/2 - raising to power 1/2 is square root. from apple's file:
// inRoot - this controls the curvature of the response. 2.0 is square root, 3.0 is cube root. But inRoot doesn't have to be integer valued, it could be 1.8 or 2.5, etc.
Essentially gives you a response between 0 and 1 again, and the curvature of that varies based on what value you set for inRoot.
I'm using Zedgraph to display multiple y axis (both YAxis and Y2Axis).
When having multple yaxis it becomes rather hard to compare curves with all the major ticks. On the picture below each curve has its own major tick:
https://dl.dropbox.com/u/70476173/problem.png
I would like the graph to share the same major ticks so that it is easy to compare the curves. I have tried with the code:
//majorTickCount = 12.0
var min = Math.Floor(yAxis.Scale.Min);
var max = Math.Ceiling(yAxis.Scale.Max);
var step = (max - min) / majorTickCount;
var wholeStep = step;
max = min + wholeStep * majorTickCount;
//yAxis.Scale.MajorStepAuto = true;
//yAxis.Scale.MajorStepAuto = false;
//yAxis.Scale.MinGrace = 0;
//yAxis.Scale.MaxGrace = 0;
yAxis.Scale.Min = min;
yAxis.Scale.Max = max;
yAxis.Scale.MajorStep = wholeStep;
yAxis.Scale.BaseTic = min;
This seems to create the desired effect, but with a problem:
https://dl.dropbox.com/u/70476173/problem2.png
The red curves 2nd and 3rd point has the value 6, but as you can see on the picture, the point lies below the majorgrid for 6. I believe the problem is that the majorstep is calculated to 2.5 and the y axis label displaying 6 should rather be 6.1 or something like that.
TL;DR: How do I make all my y axes share the same major steps
Any idea of how I can scale the y axis so that they share the same major grid?