egd_sensor_type(3) [debian man page]

EGD_SENSOR_TYPE(3)					       EEGDEV library manual						EGD_SENSOR_TYPE(3)

NAME

       egd_sensor_type, egd_sensor_name - Get the id or name of a sensor type

SYNOPSIS

       #include <eegdev.h>

       int egd_sensor_type(const char* sname);
       const char* egd_sensor_name(int stype);

DESCRIPTION

       egd_sensor_type()  returns  the	identifier code of the sensor type named sname. egd_sensor_name() is the reverse process: it retrieves the
       name of the sensor type identified by stype.

       Depending on which acquisition devices have been accessed by the library, the sensor type identifier for a given name may be different from
       a  previous program execution. However once a association has been established it is ensured that it will remain the same until the process
       termination.  Additionally, the sensor types named "eeg", "trigger" and "undefined" are always associated respectively to 0, 1 and 2.

RETURN VALUE

       In case of success, egd_sensor_type() returns a non negative value corresponding to the identifier of the sensor type called name.   Other-
       wise it returns -1.

       In case of success, egd_sensor_name() returns the name of the sensor type identified by stype. Otherwise, NULL is returned and errno is set
       accordingly.

ERRORS

       egd_sensor_type() or egd_sensor_name() will fail if:

       EINVAL sname is NULL or refers to an unknown sensor type or if stype is not a known sensor type identifier.

SEE ALSO

       egd_get_numch(3) egd_get_cap(3)

EPFL
								       2011							EGD_SENSOR_TYPE(3)

EGD_CHANNEL_INFO(3)					       EEGDEV library manual					       EGD_CHANNEL_INFO(3)

NAME

       egd_channel_info - Get various information about a particular channel

SYNOPSIS

       #include <eegdev.h>

       int egd_channel_info(const struct eegdev* dev, int stype,
			     unsigned int index, int fieldtype, ...);

DESCRIPTION

       egd_channel_info()  provides  different	type  of  information  about the channel at the index index of the group specified by stype of the
       device referenced by dev. As described for egd_acq_setup(3), stype specifies the type of channel. It must one of  the  values  returned	by
       egd_sensor_type(3).

       The  information  returned by the function is defined by the variable list of argument. This list is composed of successive couple grouping
       one field type identifier specifying the feature to be get and a pointer to a value whose type depends on the previous field type. The list
       must finish by EGD_END.

       The field identifers can be the following (The expected corresponding pointer type is provided in parenthesis):

       EGD_LABEL (char*)
	      Name of the channel. The pointed array should be long enough to hold 32 characters (including the null termination character).

       EGD_ISINT (int*)
	      Indicates whether the data provided by the channel are integer or floating point. (zero indicates floating point, non-zero indicates
	      integer).

       EGD_MM_I (int32_t*)
	      Returns in an array of 2 int32_t the minimal and maximal values that the channel can deliver (If the channel deliver floating  point
	      data, these values can be underestimated due to overflow)

       EGD_MM_F (float*)
	      Returns  in  an  array  of 2 float values the minimal and maximal values that the channel can deliver (If the channel deliver double
	      floating point data, these values can be underestimated due to overflow)

       EGD_MM_D (double*)
	      Returns in an array of 2 double values the minimal and maximal values that the channel can deliver.

       EGD_UNIT (char*)
	      Unit in which the channel data is expressed. The pointed array should be long enough to hold 16 characters (including the null  ter-
	      mination character).

       EGD_TRANSDUCTER (char*)
	      Transducter type of the sensor. The pointed array should be long enough to hold 128 characters (including the null termination char-
	      acter).

       EGD_PREFILTERING (char*)
	      Information about the filters already applied on data. The pointed array should be long enough to hold 128 characters (including the
	      null termination character).

RETURN VALUE

       The function returns 0 in case of succes. Otherwise, -1 is returned and errno is set accordingly.

ERRORS

       egd_channel_info() will fail if:

       EINVAL dev  is NULL, stype is an invalid sensor type, index is bigger than the maximal number of channel in the group, any field identifier
	      is unknown or any pointer used is NULL.

THREAD SAFETY

       egd_channel_info() is thread-safe.

SEE ALSO

       egd_acq_setup(3), egd_sensor_type(3)

EPFL
								       2010						       EGD_CHANNEL_INFO(3)