# NanoVNASaver
#
# A python program to view and export Touchstone data from a NanoVNA
# Copyright (C) 2019, 2020 Rune B. Broberg
# Copyright (C) 2020,2021 NanoVNA-Saver Authors
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
import logging
import math
import numpy as np
from PySide6.QtCore import QPoint, QRect, Qt
from PySide6.QtGui import (
QAction,
QActionGroup,
QColor,
QFontMetrics,
QMouseEvent,
QPainter,
QPaintEvent,
QPalette,
QPen,
QResizeEvent,
QShortcut,
QWheelEvent,
)
from PySide6.QtWidgets import QDialog, QInputDialog, QMenu, QSizePolicy
from .Chart import Chart, ChartPosition
logger = logging.getLogger(__name__)
MIN_IMPEDANCE = 0
MAX_IMPEDANCE = 1000
MIN_S11 = -60
MAX_S11 = 0
MIN_VSWR = 1
MAX_VSWR = 10
[docs]
class TDRChart(Chart):
max_display_length: int = 50
min_display_length: int = 0
fixed_span: bool = False
min_y_lim: float = 0.0
max_y_lim: float = 1000.0
decimals: int = 1
format_string: str = ""
fixed_values: bool = False
marker_location: int = -1
def __init__(self, name) -> None:
super().__init__(name)
self.tdrWindow: QDialog = QDialog()
self.bottomMargin = 25
self.topMargin = 20
self.setMinimumSize(300, 300)
self.setSizePolicy(
QSizePolicy(
QSizePolicy.Policy.MinimumExpanding,
QSizePolicy.Policy.MinimumExpanding,
)
)
pal = QPalette()
pal.setColor(QPalette.ColorRole.Window, Chart.color.background)
self.setPalette(pal)
self.setAutoFillBackground(True)
self.setContextMenuPolicy(Qt.ContextMenuPolicy.DefaultContextMenu)
self.menu = QMenu()
self.reset = QAction("Reset")
self.reset.triggered.connect(self.resetDisplayLimits)
self.menu.addAction(self.reset)
self.x_menu = QMenu("Length axis")
self.mode_group = QActionGroup(self.x_menu)
self.action_fixed_span = QAction("Fixed span")
self.action_fixed_span.setCheckable(True)
self.action_fixed_span.changed.connect(
lambda: self.setFixedSpan(self.action_fixed_span.isChecked())
)
self.action_automatic = QAction("Automatic")
self.action_automatic.setCheckable(True)
self.action_automatic.setChecked(True)
self.action_automatic.changed.connect(
lambda: self.setFixedSpan(self.action_fixed_span.isChecked())
)
self.mode_group.addAction(self.action_automatic)
self.mode_group.addAction(self.action_fixed_span)
self.x_menu.addAction(self.action_automatic)
self.x_menu.addAction(self.action_fixed_span)
self.x_menu.addSeparator()
self.action_set_fixed_start = QAction(
f"Start ({self.min_display_length})"
)
self.action_set_fixed_start.triggered.connect(self.setMinimumLength)
self.action_set_fixed_stop = QAction(
f"Stop ({self.max_display_length})"
)
self.action_set_fixed_stop.triggered.connect(self.setMaximumLength)
self.x_menu.addAction(self.action_set_fixed_start)
self.x_menu.addAction(self.action_set_fixed_stop)
self.y_menu = QMenu("Y axis")
self.y_mode_group = QActionGroup(self.y_menu)
self.y_action_fixed = QAction("Fixed")
self.y_action_fixed.setCheckable(True)
self.y_action_fixed.changed.connect(
lambda: self.setFixedValues(self.y_action_fixed.isChecked())
)
self.y_action_automatic = QAction("Automatic")
self.y_action_automatic.setCheckable(True)
self.y_action_automatic.setChecked(True)
self.y_action_automatic.changed.connect(
lambda: self.setFixedValues(self.y_action_fixed.isChecked())
)
self.y_mode_group.addAction(self.y_action_automatic)
self.y_mode_group.addAction(self.y_action_fixed)
self.y_menu.addAction(self.y_action_automatic)
self.y_menu.addAction(self.y_action_fixed)
self.y_menu.addSeparator()
self.y_action_set_fixed_maximum = QAction(f"Maximum ({self.max_y_lim})")
self.y_action_set_fixed_maximum.triggered.connect(self.setMaximumY)
self.y_action_set_fixed_minimum = QAction(f"Minimum ({self.min_y_lim})")
self.y_action_set_fixed_minimum.triggered.connect(self.setMinimumY)
self.y_menu.addAction(self.y_action_set_fixed_maximum)
self.y_menu.addAction(self.y_action_set_fixed_minimum)
self.menu.addMenu(self.x_menu)
self.menu.addMenu(self.y_menu)
self.menu.addSeparator()
self.menu.addAction(self.action_save_screenshot)
self.action_popout = QAction("Popout chart")
self.action_popout.triggered.connect(
lambda: self.popout_requested.emit(self)
)
self.menu.addAction(self.action_popout)
self.dim.width = self.width() - self.leftMargin - self.rightMargin
self.dim.height = self.height() - self.bottomMargin - self.topMargin
QShortcut(Qt.Key.Key_Up, self, lambda: self.pan_graph(0, 1))
QShortcut(Qt.Key.Key_Down, self, lambda: self.pan_graph(0, -1))
QShortcut(Qt.Key.Key_Left, self, lambda: self.pan_graph(1, 0))
QShortcut(Qt.Key.Key_Right, self, lambda: self.pan_graph(-1, 0))
[docs]
def pan_graph(self, x, y):
logger.debug("Moving graph %s, %s", x, y)
dx = self.dim.width / 10 * x
dy = self.dim.height / 10 * y
self.zoomTo(
self.leftMargin + dx,
self.topMargin + dy,
self.leftMargin + self.dim.width + dx,
self.topMargin + self.dim.height + dy,
)
[docs]
def isLinePlotable(self, p1, p2):
"""
Test if the line could be drawn.
This is a very simple test. Even if the result is true,
the line could still be invisible. But if the result is false,
the line is guaranteed to be invisible.
Returns
-------
False, if the line is outside the current chart area. True otherwise.
"""
if p1.x() is None or p1.y() is None or p2.x() is None or p2.y() is None:
return False
# logger.debug(f"P1 {p1}, {p2}")
horizontal = [self.leftMargin, self.width() - self.rightMargin]
x1q = np.searchsorted(horizontal, p1.x())
x2q = np.searchsorted(horizontal, p2.x())
# logger.debug(f"x1 {x1q}, {x2q}, horizontal: {horizontal}")
if x1q == x2q != 1:
# logger.debug(f" -> FALSE")
return False
vertical = [self.topMargin, self.height() - self.bottomMargin]
y1q = np.searchsorted(vertical, p1.y())
y2q = np.searchsorted(vertical, p2.y())
# logger.debug(f"y1 {y1q}, {y2q}, vertical: {vertical}")
if y1q == y2q != 1:
# logger.debug(f" -> FALSE")
return False
# logger.debug(f" -> TRUE")
return True
[docs]
def isPlotable(self, p: QPoint) -> bool:
if p.x() is None or p.y() is None:
return False
return (
self.leftMargin <= p.x() <= self.width() - self.rightMargin
and self.topMargin <= p.y() <= self.height() - self.bottomMargin
)
def _configureGraphFromFormat(self) -> None:
FORMAT_DEFAULTS = {
"|Z| (lowpass)": (
MIN_IMPEDANCE,
MAX_IMPEDANCE,
"impedance (\N{OHM SIGN})",
1,
),
"S11 (lowpass)": (MIN_S11, MAX_S11, "S11 (dB)", 1),
"VSWR (lowpass)": (MIN_VSWR, MAX_VSWR, "VSWR", 2),
"Refl (lowpass)": (-1, 1, "U", 2),
"Refl (bandpass)": (0, 1, "U", 2),
}
self.min_y_lim, self.max_y_lim, self.format_string, self.decimals = (
FORMAT_DEFAULTS[self.tdrWindow.format_dropdown.currentText()]
)
[docs]
def resetDisplayLimits(self) -> None:
self._configureGraphFromFormat()
self.fixed_span = False
self.min_display_length = 0
self.max_display_length = 100
self.fixed_values = False
self.update()
[docs]
def setFixedSpan(self, fixed_span) -> None:
self.fixed_span = fixed_span
self.update()
[docs]
def setMinimumLength(self) -> None:
min_val, selected = QInputDialog.getDouble(
self,
"Start length (m)",
"Set start length (m)",
value=self.min_display_length,
minValue=0,
decimals=1,
)
if not selected:
return
if not (self.fixed_span and min_val >= self.max_display_length):
self.min_display_length = round(min_val)
if self.fixed_span:
self.update()
[docs]
def setMaximumLength(self) -> None:
max_val, selected = QInputDialog.getDouble(
self,
"Stop length (m)",
"Set stop length (m)",
value=self.max_display_length,
minValue=0.1,
decimals=1,
)
if not selected:
return
if not (self.fixed_span and max_val <= self.min_display_length):
self.max_display_length = round(max_val)
if self.fixed_span:
self.update()
[docs]
def setFixedValues(self, fixed_values) -> None:
self.fixed_values = fixed_values
self.update()
[docs]
def setMinimumY(self) -> None:
min_val, selected = QInputDialog.getDouble(
self,
"Minimum " + self.format_string,
"Set minimum " + self.format_string,
value=self.min_y_lim,
decimals=self.decimals,
)
if not selected:
return
if not (self.fixed_values and min_val >= self.max_y_lim):
self.min_y_lim = min_val
if self.fixed_values:
self.update()
[docs]
def setMaximumY(self) -> None:
max_val, selected = QInputDialog.getDouble(
self,
"Maximum " + self.format_string,
"Set maximum " + self.format_string,
value=self.max_y_lim,
decimals=self.decimals,
)
if not selected:
return
if not (self.fixed_values and max_val <= self.min_y_lim):
self.max_y_lim = max_val
if self.fixed_values:
self.update()
[docs]
def copy(self) -> "TDRChart":
new_chart: TDRChart = super().copy()
new_chart.tdrWindow = self.tdrWindow
new_chart.min_display_length = self.min_display_length
new_chart.max_display_length = self.max_display_length
new_chart.fixed_span = self.fixed_span
new_chart.min_y_lim = self.min_y_lim
new_chart.max_y_lim = self.max_y_lim
new_chart.fixed_values = self.fixed_values
self.tdrWindow.updated.connect(new_chart.update)
return new_chart
[docs]
def wheelEvent(self, a0: QWheelEvent) -> None:
a0.accept()
super().wheelEvent(a0)
[docs]
def mouseMoveEvent(self, a0: QMouseEvent) -> None:
if not hasattr(self.tdrWindow, "td"):
return
if a0.buttons() == Qt.MouseButton.RightButton:
a0.ignore()
return
if a0.buttons() == Qt.MouseButton.MiddleButton:
# Drag the display
a0.accept()
if self.dragbox.move_x != -1 and self.dragbox.move_y != -1:
dx = self.dragbox.move_x - a0.position().x()
dy = self.dragbox.move_y - a0.position().y()
self.zoomTo(
self.leftMargin + dx,
self.topMargin + dy,
self.leftMargin + self.dim.width + dx,
self.topMargin + self.dim.height + dy,
)
self.dragbox.move_x = a0.position().x()
self.dragbox.move_y = a0.position().y()
return
if a0.modifiers() == Qt.KeyboardModifier.ControlModifier:
# Dragging a box
a0.accept()
if not self.dragbox.state:
self.dragbox.state = True
self.dragbox.pos_start = ChartPosition(
a0.position().x(), a0.position().y()
)
self.dragbox.pos = ChartPosition(
a0.position().x(), a0.position().y()
)
self.update()
return
x = a0.position().x()
absx = x - self.leftMargin
if absx < 0 or absx > self.width() - self.rightMargin:
a0.ignore()
return
a0.accept()
self.marker_location = self.lengthAtPosition(x, limit=False)
self.update()
def _draw_ticks(
self, height, _width, _x_step, min_index, qp: QPainter
) -> None:
desired_steps = math.ceil(
(self.width() - self.leftMargin - self.rightMargin) / 100
)
min_length, max_length, m_per_pixel = self._get_chart_parameters()
delta_length = max_length - min_length
step_length = delta_length / desired_steps
decimals = math.ceil(abs(math.log10(step_length)))
step_length_rounded = math.ceil(step_length * (10**decimals)) / (
10**decimals
)
start_length = (
min_length
- (min_length % step_length_rounded)
+ step_length_rounded
)
for distance in np.arange(
start_length, max_length, step_length_rounded
):
x = self.leftMargin + round((distance - min_length) / m_per_pixel)
# lines
qp.setPen(QPen(Chart.color.foreground))
qp.drawLine(x, self.topMargin, x, self.topMargin + height)
# text
qp.setPen(QPen(Chart.color.text))
self._draw_centered_hanging_text(
qp,
f"{{:.{decimals}f}} m".format(distance),
QPoint(x, self.topMargin + height),
False,
)
# text at origin
qp.setPen(QPen(Chart.color.text))
distance = self.tdrWindow.distance_axis[min_index] / 2
self._draw_centered_hanging_text(
qp,
f"{{:.{decimals}f}} m".format(distance),
QPoint(self.leftMargin, self.topMargin + height),
False,
)
def _draw_y_ticks(
self, height, width, min_impedance, max_impedance, qp: QPainter
) -> None:
y_step = (max_impedance - min_impedance) / height
y_ticks = math.floor(height / 60)
y_tick_step = height / y_ticks
for i in range(y_ticks):
y = self.bottomMargin + int(i * y_tick_step)
qp.setPen(Chart.color.foreground)
qp.drawLine(self.leftMargin, y, self.leftMargin + width, y)
y_val = max_impedance - y_step * i * y_tick_step
qp.setPen(Chart.color.text)
qp.drawText(3, y + 3, str(round(y_val, self.decimals)))
qp.setPen(Chart.color.text)
qp.drawText(
3,
self.topMargin + height + 3,
f"{round(min_impedance, self.decimals)}",
)
def _draw_max_point(
self, height, x_step, y_step, min_index, qp: QPainter
) -> None:
id_max = np.argmax(self.tdrWindow.td)
max_point = QPoint(
self.leftMargin + int((id_max - min_index) / x_step),
(self.topMargin + height)
- int(np.real(self.tdrWindow.td[id_max]) / y_step),
)
qp.setPen(self.markers[0].color)
qp.drawEllipse(max_point, 2, 2)
qp.setPen(Chart.color.text)
self._draw_centered_hanging_text(
qp,
f"{round(self.tdrWindow.distance_axis[id_max] / 2, 2)}m",
max_point,
True,
)
def _draw_marker(self, height, _x_step, _y_step, _min_index, qp: QPainter):
marker_point = QPoint(
self.positionAtLength(self.marker_location, limit=False),
(self.topMargin + height),
)
qp.setPen(Chart.color.text)
qp.drawEllipse(marker_point, 2, 2)
self._draw_centered_hanging_text(
qp, f"{self.marker_location:.3f} m", marker_point, True
)
def _draw_graph(self, height, width, qp: QPainter) -> None:
min_index = 0
max_index = math.ceil(len(self.tdrWindow.distance_axis) / 2)
if self.fixed_span:
max_length = max(0.1, self.max_display_length)
max_index = np.searchsorted(
self.tdrWindow.distance_axis, max_length * 2
)
min_index = np.searchsorted(
self.tdrWindow.distance_axis, self.min_display_length * 2
)
if max_index == min_index:
if max_index < len(self.tdrWindow.distance_axis) - 1:
max_index += 1
else:
min_index -= 1
x_step = (max_index - min_index) / width
# TODO: Limit the search to the selected span?
min_Z = np.min(self.tdrWindow.step_response_Z)
max_Z = np.max(self.tdrWindow.step_response_Z)
# Ensure that everything works even if limits are negative
min_impedance = max(self.min_y_lim, min_Z - 0.05 * np.abs(min_Z))
max_impedance = min(self.max_y_lim, max_Z + 0.05 * np.abs(max_Z))
if self.fixed_values:
min_impedance = self.min_y_lim
max_impedance = self.max_y_lim
self._draw_ticks(height, width, x_step, min_index, qp)
self._draw_y_ticks(height, width, min_impedance, max_impedance, qp)
pen = QPen(Chart.color.sweep)
pen.setWidth(self.dim.line if self.flag.draw_lines else self.dim.point)
qp.setPen(pen)
y_step = (max_impedance - min_impedance) / height
tdr_points = [
QPoint(
self.leftMargin + int((i - min_index) / x_step),
(self.topMargin + height)
- int(np.real(self.tdrWindow.td[i]) / y_step),
)
for i in range(min_index, max_index)
]
step_response_points = [
QPoint(
self.leftMargin + int((i - min_index) / x_step),
(self.topMargin + height)
- int(
(self.tdrWindow.step_response_Z[i] - min_impedance) / y_step
),
)
for i in range(min_index, max_index)
]
pen.setColor(Chart.color.sweep)
qp.setPen(pen)
if self.flag.draw_lines:
last_pt = tdr_points[0]
for point in tdr_points[1:]:
if self.isLinePlotable(last_pt, point):
qp.drawLine(last_pt, point)
last_pt = point
pen.setColor(Chart.color.sweep_secondary)
qp.setPen(pen)
last_pt = step_response_points[0]
for point in step_response_points[1:]:
if self.isLinePlotable(last_pt, point):
qp.drawLine(last_pt, point)
last_pt = point
else:
for p in tdr_points:
if self.isPlotable(p):
qp.drawPoint(p)
pen.setColor(Chart.color.sweep_secondary)
qp.setPen(pen)
for p in step_response_points:
if self.isPlotable(p):
qp.drawPoint(p)
self._draw_max_point(height, x_step, y_step, min_index, qp)
if self.marker_location != -1:
self._draw_marker(height, x_step, y_step, min_index, qp)
[docs]
def paintEvent(self, _: QPaintEvent) -> None:
qp = QPainter(self)
qp.setPen(QPen(Chart.color.text))
qp.drawText(3, 15, self.name)
width = self.width() - self.leftMargin - self.rightMargin
height = self.height() - self.bottomMargin - self.topMargin
qp.setPen(QPen(Chart.color.foreground))
qp.drawLine(
self.leftMargin - 5,
self.height() - self.bottomMargin,
self.width() - self.rightMargin,
self.height() - self.bottomMargin,
)
qp.drawLine(
self.leftMargin,
self.topMargin - 5,
self.leftMargin,
self.height() - self.bottomMargin + 5,
)
self.drawTitle(qp)
if hasattr(self.tdrWindow, "td"):
self._draw_graph(height, width, qp)
if self.dragbox.state and self.dragbox.pos[0] != -1:
self.drawDragbog(qp)
qp.end()
[docs]
def valueAtPosition(self, y: int) -> float:
if hasattr(self.tdrWindow, "td"):
height = self.height() - self.topMargin - self.bottomMargin
absy = (self.height() - y) - self.bottomMargin
if self.fixed_values:
min_impedance = self.min_y_lim
max_impedance = self.max_y_lim
else:
min_Z = float(np.min(self.tdrWindow.step_response_Z))
max_Z = float(np.max(self.tdrWindow.step_response_Z))
# Ensure that everything works even if limits are negative
min_impedance = max(
self.min_y_lim, min_Z - 0.05 * float(np.abs(min_Z))
)
max_impedance = min(
self.max_y_lim, max_Z + 0.05 * float(np.abs(max_Z))
)
y_step = (max_impedance - min_impedance) / height
return y_step * absy + min_impedance
return 0.0
def _get_chart_parameters(self):
"""
Get the currently displayed
start end length in meter and the step size in m/pixel
Returns:
float, float, float: min_length, max_length, step_size
"""
width_px = self.width() - self.leftMargin - self.rightMargin
min_length = self.min_display_length if self.fixed_span else 0
max_length = (
self.max_display_length
if self.fixed_span
else (
self.tdrWindow.distance_axis[
math.ceil(len(self.tdrWindow.distance_axis) / 2)
]
/ 2
)
)
x_step = float(max_length - min_length) / width_px
return min_length, max_length, x_step
[docs]
def lengthAtPosition(self, x: int, limit=True):
if not hasattr(self.tdrWindow, "td"):
return 0
width_px = self.width() - self.leftMargin - self.rightMargin
min_length, max_length, x_step = self._get_chart_parameters()
absx = x - self.leftMargin
if limit and absx < 0:
return float(min_length)
return float(
max_length
if limit and absx > width_px
else absx * x_step + min_length
)
[docs]
def positionAtLength(self, length, limit=True):
if not hasattr(self.tdrWindow, "td"):
return 0
min_length, _, x_step = self._get_chart_parameters()
if limit:
return self.leftMargin # really? not sure how to handle this
pos = ((length - min_length) / x_step) + self.leftMargin
return pos
[docs]
def zoomTo(self, x1, y1, x2, y2) -> None:
logger.debug(
"Zoom to (x,y) by (x,y): (%d, %d) by (%d, %d)", x1, y1, x2, y2
)
val1 = self.valueAtPosition(y1)
val2 = self.valueAtPosition(y2)
if val1 != val2:
self.min_y_lim = round(min(val1, val2), 3)
self.max_y_lim = round(max(val1, val2), 3)
self.setFixedValues(True)
x_min = min(x1, x2)
x_max = max(x1, x2)
# test if we reach the negative length range -> adjust to zero
if self.lengthAtPosition(x_min, limit=False) < 0:
at_zero = self.positionAtLength(0, limit=False)
x_max = x_max + (at_zero - x_min)
x_min = at_zero
if self.lengthAtPosition(x_max, limit=False) > (
self.tdrWindow.distance_axis[-1] / 2
):
at_end = self.positionAtLength(
self.tdrWindow.distance_axis[-1] / 2, limit=False
)
x_min = x_min + (at_end - x_max)
x_max = at_end
len1 = max(0, self.lengthAtPosition(x_min, limit=False))
len2 = max(0, self.lengthAtPosition(x_max, limit=False))
if len1 >= 0 and len2 >= 0 and len1 != len2:
self.min_display_length = min(len1, len2)
self.max_display_length = max(len1, len2)
self.setFixedSpan(True)
self.update()
[docs]
def resizeEvent(self, a0: QResizeEvent) -> None:
super().resizeEvent(a0)
self.dim.width = self.width() - self.leftMargin - self.rightMargin
self.dim.height = self.height() - self.bottomMargin - self.topMargin
def _draw_centered_hanging_text(
self, qp, text, center: QPoint, above: bool
):
# Measure text size
fm = QFontMetrics(qp.font())
text_width = fm.horizontalAdvance(text)
text_height = fm.height()
# Compute top-left position for centered text
x = center.x() - text_width // 2
y = center.y() + (-text_height / 4 if above else text_height)
# enhance readability when drawn over ticks
margin = 5
rect = QRect(
x - margin, y - text_height, text_width + 2 * margin, text_height
)
semi_transparent_bg = QColor(Chart.color.background)
semi_transparent_bg.setAlpha(150)
qp.fillRect(rect, semi_transparent_bg)
# draw the length
qp.drawText(x, y, text) # Draw text at computed position
[docs]
def get_fft_points(self):
"""
Get the number of FFT points. When we draw with lines as opposed to
separate points a lower (but still very high resolution) makes
the GUI more responsive.
"""
return 2**12 if self.flag.draw_lines else 2**14