Math Channel

Math channel operations and expressions

Math channel operations for waveform analysis.

MathOperations

Static methods for mathematical operations on waveforms.

add staticmethod

add(waveform1, waveform2)

Add two waveforms.

Parameters:

Name	Type	Description	Default
waveform1		First waveform	required
waveform2		Second waveform	required

Returns:

Type	Description
	Result waveform with voltage = v1 + v2

Source code in scpi_control/math_channel.py

@staticmethod
def add(waveform1, waveform2):
    """Add two waveforms.

    Args:
        waveform1: First waveform
        waveform2: Second waveform

    Returns:
        Result waveform with voltage = v1 + v2
    """
    if waveform1 is None or waveform2 is None:
        return None

    return MathOperations._create_result_waveform(waveform1, waveform1.voltage + waveform2.voltage)

subtract staticmethod

subtract(waveform1, waveform2)

Subtract two waveforms.

Parameters:

Name	Type	Description	Default
waveform1		First waveform	required
waveform2		Second waveform	required

Returns:

Type	Description
	Result waveform with voltage = v1 - v2

Source code in scpi_control/math_channel.py

@staticmethod
def subtract(waveform1, waveform2):
    """Subtract two waveforms.

    Args:
        waveform1: First waveform
        waveform2: Second waveform

    Returns:
        Result waveform with voltage = v1 - v2
    """
    if waveform1 is None or waveform2 is None:
        return None

    return MathOperations._create_result_waveform(waveform1, waveform1.voltage - waveform2.voltage)

multiply staticmethod

multiply(waveform1, waveform2)

Multiply two waveforms.

Parameters:

Name	Type	Description	Default
waveform1		First waveform	required
waveform2		Second waveform	required

Returns:

Type	Description
	Result waveform with voltage = v1 * v2

Source code in scpi_control/math_channel.py

@staticmethod
def multiply(waveform1, waveform2):
    """Multiply two waveforms.

    Args:
        waveform1: First waveform
        waveform2: Second waveform

    Returns:
        Result waveform with voltage = v1 * v2
    """
    if waveform1 is None or waveform2 is None:
        return None

    return MathOperations._create_result_waveform(waveform1, waveform1.voltage * waveform2.voltage)

divide staticmethod

divide(waveform1, waveform2, epsilon=1e-12)

Divide two waveforms.

Parameters:

Name	Type	Description	Default
waveform1		First waveform (numerator)	required
waveform2		Second waveform (denominator)	required
epsilon		Small value to prevent division by zero	1e-12

Returns:

Type	Description
	Result waveform with voltage = v1 / v2

Source code in scpi_control/math_channel.py

@staticmethod
def divide(waveform1, waveform2, epsilon=1e-12):
    """Divide two waveforms.

    Args:
        waveform1: First waveform (numerator)
        waveform2: Second waveform (denominator)
        epsilon: Small value to prevent division by zero

    Returns:
        Result waveform with voltage = v1 / v2
    """
    if waveform1 is None or waveform2 is None:
        return None

    # Prevent division by zero
    denominator = np.where(np.abs(waveform2.voltage) < epsilon, epsilon, waveform2.voltage)

    return MathOperations._create_result_waveform(waveform1, waveform1.voltage / denominator)

integrate staticmethod

integrate(waveform)

Integrate a waveform (cumulative sum).

Parameters:

Name	Type	Description	Default
waveform		Input waveform	required

Returns:

Type	Description
	Result waveform with integrated values

Source code in scpi_control/math_channel.py

@staticmethod
def integrate(waveform):
    """Integrate a waveform (cumulative sum).

    Args:
        waveform: Input waveform

    Returns:
        Result waveform with integrated values
    """
    if waveform is None:
        return None

    # Calculate time step
    dt = np.mean(np.diff(waveform.time)) if len(waveform.time) > 1 else 1.0

    # Cumulative integration using trapezoidal rule
    integrated = np.cumsum(waveform.voltage) * dt

    return MathOperations._create_result_waveform(waveform, integrated)

differentiate staticmethod

differentiate(waveform)

Differentiate a waveform.

Parameters:

Name	Type	Description	Default
waveform		Input waveform	required

Returns:

Type	Description
	Result waveform with differentiated values

Source code in scpi_control/math_channel.py

@staticmethod
def differentiate(waveform):
    """Differentiate a waveform.

    Args:
        waveform: Input waveform

    Returns:
        Result waveform with differentiated values
    """
    if waveform is None:
        return None

    # Calculate derivative using numpy gradient (more stable than diff)
    dt = np.mean(np.diff(waveform.time)) if len(waveform.time) > 1 else 1.0
    differentiated = np.gradient(waveform.voltage, dt)

    return MathOperations._create_result_waveform(waveform, differentiated)

scale staticmethod

scale(waveform, factor)

Scale a waveform by a constant factor.

Parameters:

Name	Type	Description	Default
waveform		Input waveform	required
factor		Scaling factor	required

Returns:

Type	Description
	Result waveform with voltage = v * factor

Source code in scpi_control/math_channel.py

@staticmethod
def scale(waveform, factor):
    """Scale a waveform by a constant factor.

    Args:
        waveform: Input waveform
        factor: Scaling factor

    Returns:
        Result waveform with voltage = v * factor
    """
    if waveform is None:
        return None

    return MathOperations._create_result_waveform(waveform, waveform.voltage * factor)

offset staticmethod

offset(waveform, offset_value)

Add a DC offset to a waveform.

Parameters:

Name	Type	Description	Default
waveform		Input waveform	required
offset_value		Offset to add	required

Returns:

Type	Description
	Result waveform with voltage = v + offset

Source code in scpi_control/math_channel.py

@staticmethod
def offset(waveform, offset_value):
    """Add a DC offset to a waveform.

    Args:
        waveform: Input waveform
        offset_value: Offset to add

    Returns:
        Result waveform with voltage = v + offset
    """
    if waveform is None:
        return None

    return MathOperations._create_result_waveform(waveform, waveform.voltage + offset_value)

abs_value staticmethod

abs_value(waveform)

Absolute value of a waveform.

Parameters:

Name	Type	Description	Default
waveform		Input waveform	required

Returns:

Type	Description
	Result waveform with voltage = |v|

Source code in scpi_control/math_channel.py

@staticmethod
def abs_value(waveform):
    """Absolute value of a waveform.

    Args:
        waveform: Input waveform

    Returns:
        Result waveform with voltage = |v|
    """
    if waveform is None:
        return None

    return MathOperations._create_result_waveform(waveform, np.abs(waveform.voltage))

invert staticmethod

invert(waveform)

Invert a waveform.

Parameters:

Name	Type	Description	Default
waveform		Input waveform	required

Returns:

Type	Description
	Result waveform with voltage = -v

Source code in scpi_control/math_channel.py

@staticmethod
def invert(waveform):
    """Invert a waveform.

    Args:
        waveform: Input waveform

    Returns:
        Result waveform with voltage = -v
    """
    if waveform is None:
        return None

    return MathOperations._create_result_waveform(waveform, -waveform.voltage)

MathChannel

MathChannel(scope, name: str)

Math channel for performing operations on oscilloscope waveforms.

Supports expressions like: - "C1 + C2" - "C1 - C2" - "C1 * C2" - "C1 / C2" - "INTG(C1)" - integrate - "DIFF(C1)" - differentiate - "ABS(C1)" - absolute value - "INV(C1)" - invert - "2 * C1 + 1" - scale and offset

Initialize math channel.

Parameters:

Name	Type	Description	Default
scope		Parent oscilloscope instance	required
name	str	Math channel name (e.g., "M1", "M2")	required

Source code in scpi_control/math_channel.py

def __init__(self, scope, name: str):
    """Initialize math channel.

    Args:
        scope: Parent oscilloscope instance
        name: Math channel name (e.g., "M1", "M2")
    """
    self.scope = scope
    self.name = name
    self.expression = ""
    self.enabled = False
    self._result_waveform = None

    logger.info(f"Math channel {name} initialized")

set_expression

set_expression(expression: str)

Set the math expression.

Parameters:

Name	Type	Description	Default
expression	str	Math expression string	required

Source code in scpi_control/math_channel.py

def set_expression(self, expression: str):
    """Set the math expression.

    Args:
        expression: Math expression string
    """
    self.expression = expression.strip()
    logger.info(f"Math channel {self.name} expression set to: {self.expression}")

enable

enable()

Enable the math channel.

Source code in scpi_control/math_channel.py

def enable(self):
    """Enable the math channel."""
    self.enabled = True
    logger.info(f"Math channel {self.name} enabled")

disable

disable()

Disable the math channel.

Source code in scpi_control/math_channel.py

def disable(self):
    """Disable the math channel."""
    self.enabled = False
    self._result_waveform = None
    logger.info(f"Math channel {self.name} disabled")

compute

compute(waveforms: Dict[str, any]) -> Optional[any]

Compute the math channel result.

Parameters:

Name	Type	Description	Default
waveforms	Dict[str, any]	Dictionary of channel_name -> waveform	required

Returns:

Type	Description
Optional[any]	Computed waveform or None if disabled/error

Source code in scpi_control/math_channel.py

def compute(self, waveforms: Dict[str, any]) -> Optional[any]:
    """Compute the math channel result.

    Args:
        waveforms: Dictionary of channel_name -> waveform

    Returns:
        Computed waveform or None if disabled/error
    """
    if not self.enabled or not self.expression:
        return None

    try:
        result = self._evaluate_expression(self.expression, waveforms)
        self._result_waveform = result
        return result
    except Exception as e:
        logger.error(f"Math channel {self.name} computation error: {e}")
        return None

get_result

get_result()

Get the most recent computation result.

Returns:

Type	Description
	Result waveform or None

Source code in scpi_control/math_channel.py

def get_result(self):
    """Get the most recent computation result.

    Returns:
        Result waveform or None
    """
    return self._result_waveform

See Also

• Oscilloscope - Main oscilloscope control class for SCPI communication
• Waveform - Waveform acquisition and data handling