A frequency characteristic measurement device that measures the frequency characteristic of a measurement target includes: a multi-sine signal generation unit that generates a multi-sine signal; a sweep sinusoidal wave generation unit that generates a plurality of sweep sinusoidal waves; an input signal switching unit that selects any one of the multi-sine signal and the sweep sinusoidal waves so as to input the selected one to the measurement target; a data acquisition unit that acquires, at a predetermined sampling frequency, sampling data of an input signal which is input to the measurement target and sampling data of an output signal which is output from the measurement target; and a characteristic calculation unit that calculates a frequency characteristic including the gain and the phase of the input and output signals in the measurement target from the sampling data of the input and output acquired.

A curve fitting method, apparatus and device based on a drawing tool for improving the accuracy of curve fitting. The method includes: determining a fitting area containing the original curve, in the fitting area, performing at least one sub-fitting operation on the original curve until the end condition of the curve fitting is satisfied, and generating a fitting curve corresponding to the original curve based on the fitting curve corresponding to each sub-fitting operation. This method can fit the original curve segments in the fitting area, which improves the accuracy of the obtained fitting curve.

A trigonometric function calculating device includes: an address generator that generates an address signal that is formed from plural bit strings and corresponds to a phase; a trigonometric function table that stores first sines and first cosines that respectively correspond to phases expressed by upper bits of the address signals, and second sines and a second cosines that respectively correspond to phases expressed by lower bits of the address signals; a calculation circuit that outputs, as a calculated value, a sine that corresponds to the address signal by calculating processing using the first sine, the first cosine, the second sine and the second cosine that correspond to the address signal and have been extracted by referring to the trigonometric function table; and a correcting section that corrects the calculated value on the basis of a correction value corresponding to the address signal.

A computer-implement method of predicting a drag area (as function of air-attack angle) of a vehicle combination after hypothetically changing an exterior shape of the vehicle combination from a first exterior shape to a second exterior shape is provided. The method includes obtaining a first drag area function, obtaining a first projected area function, obtaining a second projected area function, and predicting a second drag area function based on a rescaling of the first drag area function by a ratio of the second projected area function to the first projected area function.

Examples described herein relate to instructions to request performance of tanh and sigmoid instructions. For example, a compiler can generate native tanh instructions to perform tanh. In some examples, a tanh function can be compiled into instructions that include an instruction to perform either tanh(input) or tanh(input)/input depending on a value of the input to generate an intermediate output; an instruction to cause a performance of generation of scale factor based on the input; and an instruction to cause performance of a multiplication operation on the intermediate result with the scale factor. For example, a sigmoid function can be compiled to cause a math pipeline to perform a range check and performs operations based on a range.

A method of measuring a movement, the method comprising the steps of: acquiring and digitizing both a first measurement voltage across the terminals of a first secondary winding and also a second measurement voltage across the terminals of a second secondary winding of an inductive movement sensor; multiplying the first measurement voltage by itself in order to obtain a first component of a crossed vector, multiplying the second measurement voltage by itself in order to obtain a second component of the crossed vector, and multiplying together the first measurement voltage and the second measurement voltage in order to obtain a third component of the crossed vector; applying the crossed vector as input to a lowpass filter in order to obtain a filtered vector, and estimating the movement from the components of the filtered vector.

The present embodiments relate to integrated circuits with circuitry that implements floating-point trigonometric functions. The circuitry may include an approximation circuit that generates an approximation of the output of the trigonometric functions, a storage circuit that stores predetermined output values of the trigonometric functions, and a selector circuit that selects between different possible output values based on a control signal from a control circuit. In some embodiments, the circuitry may include a mapping circuit and a restoration circuit. The mapping circuit may map an input value from an original quadrant of the trigonometric circle to a predetermined input interval, and the restoration circuit may map the output value selected by the selection circuit back to the original quadrant of the trigonometric circle. If desired, the circuitry may be implemented in specialized processing blocks.

A trigonometric function calculating device includes: an address generator that generates an address signal that is formed from plural bit strings and corresponds to a phase; a trigonometric function table that stores first sines and first cosines that respectively correspond to phases expressed by upper bits of the address signals, and second sines and a second cosines that respectively correspond to phases expressed by lower bits of the address signals; a calculation circuit that outputs, as a calculated value, a sine that corresponds to the address signal by calculating processing using the first sine, the first cosine, the second sine and the second cosine that correspond to the address signal and have been extracted by referring to the trigonometric function table; and a correcting section that corrects the calculated value on the basis of a correction value corresponding to the address signal.

An arithmetic processing device includes a coefficient memory storing coefficients of a Taylor series expansion of a trigonometric function, a multiply-add arithmetic unit, a first bypass path supplying an output of the multiply-add arithmetic unit to a register file, an OR circuit calculating OR of a sign bit of the output of the multiply-add arithmetic unit and a least significant bit of a second input, a first selector selecting either a first input y or a value 1.0 an EOR circuit calculating an EOR of a first bit of the second input and a sign bit of an output of the first selector, and a second bypass path supplying the least significant bit of the second input to a coefficient selector. The multiply-add arithmetic unit executes an auxiliary instruction repeatedly while modifying a coefficient index from a maximum value to a minimum value to calculate sin (x).

A frequency characteristic measurement device that measures the frequency characteristic of a measurement target includes: a multi-sine signal generation unit that generates a multi-sine signal; a sweep sinusoidal wave generation unit that generates a plurality of sweep sinusoidal waves; an input signal switching unit that selects any one of the multi-sine signal and the sweep sinusoidal waves so as to input the selected one to the measurement target; a data acquisition unit that acquires, at a predetermined sampling frequency, sampling data of an input signal which is input to the measurement target and sampling data of an output signal which is output from the measurement target; and a characteristic calculation unit that calculates a frequency characteristic including the gain and the phase of the input and output signals in the measurement target from the sampling data of the input and output acquired.